My players LOVE adopting monsters, so far they've attempted to recruit a goblin, one player stole a Dire Wolf from a bugbear with an incredible animal handling check, and the other straight up formed a mind bond with a Grick. I've allowed them to keep their pets and they're using the standard monster stat block for their respective pets' stats.
The question I have is how would you all handle leveling monsters up, and when is the appropriate time to do so? The biggest challenge I have with this is adjusting encounters - right now they have two extra creatures on their side that skews things. I've been supplementing with just giving monsters more HP but that's not nearly as interesting as it could be. How would I factor that in? Do I treat the monsters as PCs to determine APL?
It's worth stating I'm a pretty loosey goosey DM - I want to challenge my players but I don't want to take the fun out of it. I let them do all kinds of wacky things as long as they can justify it (the one that tamed the Grick allowed themselves to gain a point of exhaustion to stay up all night and turn the Grick pink using magic), so I'd like them to keep their pets, but I don't want the encounters to become easier as a result, and I also don't want their pets becoming weaker and weaker as the campaign goes on.
Hmm. Only certain monsters can level. They are consider full party members for the encounter but they gain 1/4 of the xp. Either give them class levels. Or simply add 1 hp, +1 to hit, and +1 damage per level. When the companion gets better than the pc, the companion leaves. Why do you think the Doctor goes through some many companions.
One of my PC’s charmed and adopted a wolf. I don’t have the wolf level, due to it acting on instinct not experience. It gets its stat block and that’s it. There may come a time when baddies are too much of a risk for their wolf companion and the group will have to make a choice whether to risk the wolf’s life & waste health potions or release the wolf back into the wilds.
Hmm. Only certain monsters can level. They are consider full party members for the encounter but they gain 1/4 of the xp. Either give them class levels. Or simply add 1 hp, +1 to hit, and +1 damage per level. When the companion gets better than the pc, the companion leaves. Why do you think the Doctor goes through some many companions.
Because they are tired of almost getting killed on repeat occasions?
You say you are a loosey goosey DM, and you want your players to have "fun", and now you are seeing what the result of your actions are.
First off, monsters don't level up. Even a Paladin's Warhorse (or any Steed) does not level up, ever.
As for the action economy and encounter level problem you have created for yourself, well good luck. Not many tables exist when you have multiple monsters of varying CR levels fighting alongside the players. The smartest thing you can do is say the monsters are not smart enough to engage in combat intelligently, and don't include them in the Initiative Phase, but they are available to be hit by area effect spells. If you REALLY want to keep these monsters in the game, tell the players that for every attack the monster makes, the player forgoes an attack.
D&D for many years, many editions, have struggled with having monsters as companions, essentially NPC's. You are seeing why. BTW, if you have a Ranger Beastmaster in your group, he must be thrilled that you just blew away his special features. You really should read carefully that subclass to get a sense of how weak these companions should be.
My players LOVE adopting monsters, so far they've attempted to recruit a goblin, one player stole a Dire Wolf from a bugbear with an incredible animal handling check, and the other straight up formed a mind bond with a Grick. I've allowed them to keep their pets and they're using the standard monster stat block for their respective pets' stats.
The question I have is how would you all handle leveling monsters up, and when is the appropriate time to do so? The biggest challenge I have with this is adjusting encounters - right now they have two extra creatures on their side that skews things. I've been supplementing with just giving monsters more HP but that's not nearly as interesting as it could be. How would I factor that in? Do I treat the monsters as PCs to determine APL?
It's worth stating I'm a pretty loosey goosey DM - I want to challenge my players but I don't want to take the fun out of it. I let them do all kinds of wacky things as long as they can justify it (the one that tamed the Grick allowed themselves to gain a point of exhaustion to stay up all night and turn the Grick pink using magic), so I'd like them to keep their pets, but I don't want the encounters to become easier as a result, and I also don't want their pets becoming weaker and weaker as the campaign goes on.
I think you could take a look at the artificer's Iron Defender and how those gain power when the artificer levels. I wouldn't let it increase as much as that, as that's still a bit of a class feature and you don't want to make those entirely useless. Maybe swap out the mod for the iron defender (I think its int, haven't double checked) for their animal handling modifier?
You say you are a loosey goosey DM, and you want your players to have "fun", and now you are seeing what the result of your actions are.
First off, monsters don't level up. Even a Paladin's Warhorse (or any Steed) does not level up, ever.
As for the action economy and encounter level problem you have created for yourself, well good luck. Not many tables exist when you have multiple monsters of varying CR levels fighting alongside the players. The smartest thing you can do is say the monsters are not smart enough to engage in combat intelligently, and don't include them in the Initiative Phase, but they are available to be hit by area effect spells. If you REALLY want to keep these monsters in the game, tell the players that for every attack the monster makes, the player forgoes an attack.
D&D for many years, many editions, have struggled with having monsters as companions, essentially NPC's. You are seeing why. BTW, if you have a Ranger Beastmaster in your group, he must be thrilled that you just blew away his special features. You really should read carefully that subclass to get a sense of how weak these companions should be.
God forbid players/dm's having fun playing the game, that would entirely ruin the game.
Whatever campaign you are doing, I recommend having the players either buy or hire a farm outside of their main town/city, where they can “stash” charmed creatures and put them in a protected place. This way, they can enjoy charming new beasts as their adventure continues, and you don’t have to worry about leveling something and making more work for yourself. At the end of the campaign, they can revisit the memories and their menagerie... maybe have the caretakers/janitorial staff be the charmed goblins. That way you aren’t the “bad DM” for killing wolfie.
Something I've seen is to have the stat boosts tied to proficiency. So when a characters' proficiency bonus goes up by one the creatures relative stats increase as well.
That said, I think it just depends on the creature. A goblin, obviously, could simply be upgraded to a full-on PC goblin, with all the stat benefits that implies. I'd start it at level 1, though, to reflect the fact that it's not as well trained as the rest of the party. Maybe it could take on the same class as whichever player originally adopted it, since I assume that's the training it would get.
The biggest problem with just letting PC pets remain with the same stats they started with is, after a certain point... they're just gonna get caught in an AOE and die. Maybe rather than worry about making their pets stronger, you should just give them some means of preventing their pets from dying outright. There was something in Critical Role where the Ranger eventually got a magic amulet that could safely house a living creature, and when that creature drops to 0 HP it immediately got teleported back into the amulet's demi-plane and became stabilized. It could either sleep off the injury for the length of a long rest or be let out after combat completed to be healed. I'm not saying you should give your party the exact same item, but something like that which makes it safer to travel with weaker companions could help preserve the fun of picking up pets without having to do a lot of rejiggering of stats to make sure they don't get killed too easily.
You say you are a loosey goosey DM, and you want your players to have "fun", and now you are seeing what the result of your actions are.
I heavily prioritize my players' enjoyment over sticking with rules, because the point of it all is that it's a game. The kinds of things I allow to happen in my home game don't transfer to when I DM AL, where there needs to be an even playing field. We don't have a ranger in our party, so no, I have not robbed a player the Beastmaster trait. The reason I asked this question in the first place is so I can work WITH my players instead of against them, and still provide some semblance of a challenge so that their victories are gratifying.
Hmm. Only certain monsters can level. They are consider full party members for the encounter but they gain 1/4 of the xp. Either give them class levels. Or simply add 1 hp, +1 to hit, and +1 damage per level.
I think you could take a look at the artificer's Iron Defender and how those gain power when the artificer levels. I wouldn't let it increase as much as that, as that's still a bit of a class feature and you don't want to make those entirely useless. Maybe swap out the mod for the iron defender (I think its int, haven't double checked) for their animal handling modifier?
Something I've seen is to have the stat boosts tied to proficiency. So when a characters' proficiency bonus goes up by one the creatures relative stats increase as well.
Oh I like these! I'll have a closer investigation of the Iron Defender and see if I can work out a system that works, otherwise I think the proficiency bonus idea is fantastic. I definitely don't want the monsters to be as strong or stronger than the players themselves, so a 1/4 exp system would work out super well. It would probably also be worth capping how strong certain monsters could get so I don't end up with some insane lv20 Dire Wolf LOL.
Maybe rather than worry about making their pets stronger, you should just give them some means of preventing their pets from dying outright. There was something in Critical Role where the Ranger eventually got a magic amulet that could safely house a living creature, and when that creature drops to 0 HP it immediately got teleported back into the amulet's demi-plane and became stabilized.
Oh yeah, Vex had basically a pokeball to pull Trinket into lol. I think if it comes to that I wouldn't mind stocking a magic shop with a similar magic item. Will keep that one in the ol' back pocket of possibilities.
Whatever campaign you are doing, I recommend having the players either buy or hire a farm outside of their main town/city, where they can “stash” charmed creatures and put them in a protected place. This way, they can enjoy charming new beasts as their adventure continues, and you don’t have to worry about leveling something and making more work for yourself. At the end of the campaign, they can revisit the memories and their menagerie... maybe have the caretakers/janitorial staff be the charmed goblins. That way you aren’t the “bad DM” for killing wolfie.
just a thought.
I really like this idea. One of my players DID express that her PC would probably obsessively collect creatures that match her aesthetic (ofc, granted she passes her checks to do so), which giving them a ranch/etc at their home base could allow for more pets, but maybe also specify that they can only bring one "combat pet" at a time, and in order to retrieve it they'd have to physically visit their home base. It'll also wonderfully complicate things once they start using teleportation to get around and they have to make decisions on which pets are worth bringing along.
I am, in general, trying to deter them from just adopting everything so I don't have a billion things to keep track of, but these are some great starting points. Thanks guys!
You say you are a loosey goosey DM, and you want your players to have "fun", and now you are seeing what the result of your actions are.
I heavily prioritize my players' enjoyment over sticking with rules, because the point of it all is that it's a game. The kinds of things I allow to happen in my home game don't transfer to when I DM AL, where there needs to be an even playing field. We don't have a ranger in our party, so no, I have not robbed a player the Beastmaster trait. The reason I asked this question in the first place is so I can work WITH my players instead of against them, and still provide some semblance of a challenge so that their victories are gratifying.
Hmm. Only certain monsters can level. They are consider full party members for the encounter but they gain 1/4 of the xp. Either give them class levels. Or simply add 1 hp, +1 to hit, and +1 damage per level.
I think you could take a look at the artificer's Iron Defender and how those gain power when the artificer levels. I wouldn't let it increase as much as that, as that's still a bit of a class feature and you don't want to make those entirely useless. Maybe swap out the mod for the iron defender (I think its int, haven't double checked) for their animal handling modifier?
Something I've seen is to have the stat boosts tied to proficiency. So when a characters' proficiency bonus goes up by one the creatures relative stats increase as well.
Oh I like these! I'll have a closer investigation of the Iron Defender and see if I can work out a system that works, otherwise I think the proficiency bonus idea is fantastic. I definitely don't want the monsters to be as strong or stronger than the players themselves, so a 1/4 exp system would work out super well. It would probably also be worth capping how strong certain monsters could get so I don't end up with some insane lv20 Dire Wolf LOL.
Maybe rather than worry about making their pets stronger, you should just give them some means of preventing their pets from dying outright. There was something in Critical Role where the Ranger eventually got a magic amulet that could safely house a living creature, and when that creature drops to 0 HP it immediately got teleported back into the amulet's demi-plane and became stabilized.
Oh yeah, Vex had basically a pokeball to pull Trinket into lol. I think if it comes to that I wouldn't mind stocking a magic shop with a similar magic item. Will keep that one in the ol' back pocket of possibilities.
Whatever campaign you are doing, I recommend having the players either buy or hire a farm outside of their main town/city, where they can “stash” charmed creatures and put them in a protected place. This way, they can enjoy charming new beasts as their adventure continues, and you don’t have to worry about leveling something and making more work for yourself. At the end of the campaign, they can revisit the memories and their menagerie... maybe have the caretakers/janitorial staff be the charmed goblins. That way you aren’t the “bad DM” for killing wolfie.
just a thought.
I really like this idea. One of my players DID express that her PC would probably obsessively collect creatures that match her aesthetic (ofc, granted she passes her checks to do so), which giving them a ranch/etc at their home base could allow for more pets, but maybe also specify that they can only bring one "combat pet" at a time, and in order to retrieve it they'd have to physically visit their home base. It'll also wonderfully complicate things once they start using teleportation to get around and they have to make decisions on which pets are worth bringing along.
I am, in general, trying to deter them from just adopting everything so I don't have a billion things to keep track of, but these are some great starting points. Thanks guys!
When they start charming a few exotic creatures have a little fun and make the farm retrofitted into an amusement park. Then you can write a home brew Jurassic Park one-shot where the charmed animals get loose. Could be a TON of fun and a great way to toss in a few fun pop Culture jokes... have the security goblin be a fat goblin named D’Nes N’dree and have him eaten by one of the escapees.
You say you are a loosey goosey DM, and you want your players to have "fun", and now you are seeing what the result of your actions are.
I heavily prioritize my players' enjoyment over sticking with rules, because the point of it all is that it's a game. The kinds of things I allow to happen in my home game don't transfer to when I DM AL, where there needs to be an even playing field. We don't have a ranger in our party, so no, I have not robbed a player the Beastmaster trait. The reason I asked this question in the first place is so I can work WITH my players instead of against them, and still provide some semblance of a challenge so that their victories are gratifying.
Hmm. Only certain monsters can level. They are consider full party members for the encounter but they gain 1/4 of the xp. Either give them class levels. Or simply add 1 hp, +1 to hit, and +1 damage per level.
I think you could take a look at the artificer's Iron Defender and how those gain power when the artificer levels. I wouldn't let it increase as much as that, as that's still a bit of a class feature and you don't want to make those entirely useless. Maybe swap out the mod for the iron defender (I think its int, haven't double checked) for their animal handling modifier?
Something I've seen is to have the stat boosts tied to proficiency. So when a characters' proficiency bonus goes up by one the creatures relative stats increase as well.
Oh I like these! I'll have a closer investigation of the Iron Defender and see if I can work out a system that works, otherwise I think the proficiency bonus idea is fantastic. I definitely don't want the monsters to be as strong or stronger than the players themselves, so a 1/4 exp system would work out super well. It would probably also be worth capping how strong certain monsters could get so I don't end up with some insane lv20 Dire Wolf LOL.
Maybe rather than worry about making their pets stronger, you should just give them some means of preventing their pets from dying outright. There was something in Critical Role where the Ranger eventually got a magic amulet that could safely house a living creature, and when that creature drops to 0 HP it immediately got teleported back into the amulet's demi-plane and became stabilized.
Oh yeah, Vex had basically a pokeball to pull Trinket into lol. I think if it comes to that I wouldn't mind stocking a magic shop with a similar magic item. Will keep that one in the ol' back pocket of possibilities.
Whatever campaign you are doing, I recommend having the players either buy or hire a farm outside of their main town/city, where they can “stash” charmed creatures and put them in a protected place. This way, they can enjoy charming new beasts as their adventure continues, and you don’t have to worry about leveling something and making more work for yourself. At the end of the campaign, they can revisit the memories and their menagerie... maybe have the caretakers/janitorial staff be the charmed goblins. That way you aren’t the “bad DM” for killing wolfie.
just a thought.
I really like this idea. One of my players DID express that her PC would probably obsessively collect creatures that match her aesthetic (ofc, granted she passes her checks to do so), which giving them a ranch/etc at their home base could allow for more pets, but maybe also specify that they can only bring one "combat pet" at a time, and in order to retrieve it they'd have to physically visit their home base. It'll also wonderfully complicate things once they start using teleportation to get around and they have to make decisions on which pets are worth bringing along.
I am, in general, trying to deter them from just adopting everything so I don't have a billion things to keep track of, but these are some great starting points. Thanks guys!
I love this! You have found something your player loves about the game, and are working with it!
One of my players wanted to adopt everything too. It started when they had to take out some ice salamander nest, and as the rest of the players smashed the eggs, he yelled, "Wait! I want one!" and he rescued it. And I was like, sure, but it's gonna be a tiny creature--you're not getting a mighty dragon thing. He didn't care.
He hatched it, it sat on his shoulder, and he'd feed it popsicles in town. It did 1 point of cold damage with its mini breath weapon. As long as it stayed on his shoulder, I never specifically targeted it (we sort of treated it like equipment in that regard).
My player wasn't looking for some crazy game breaking advantage, he just found the idea of magic pets really appealing.
It was pretty much his favorite part of the game, so I'd periodically add creatures for him to find. I eventually did the menagerie thing, where he stashed all but 1 creature per adventure, and it worked out great. Otherwise, he was just covered with little critters!
There was something in Critical Role where the Ranger eventually got a magic amulet that could safely house a living creature, and when that creature drops to 0 HP it immediately got teleported back into the amulet's demi-plane and became stabilized. It could either sleep off the injury for the length of a long rest or be let out after combat completed to be healed. I'm not saying you should give your party the exact same item, but something like that which makes it safer to travel with weaker companions could help preserve the fun of picking up pets without having to do a lot of rejiggering of stats to make sure they don't get killed too easily.
If you’re trying to level them, make sure the players understand they are getting a share of the xp, meaning the PCs level more slowly. Often, that discourages players from adopting a zoo/army. And it shouldn’t be up to you to keep track of them. If the players want pets, it’s up to the players to track them.
Also, as has been said above, you are basically giving away a class feature for free. Arguably one of the weaker class features, but still a class feature. It will make encounters easier for the players. You might want to find a way to force them to invest some kind of resources into them to balance it out.
By RAW, they are not PCs and therefore shouldn’t get death saves, 0hp = dead. You should decide if you are going to follow that or not and be sure to tell the players either way. And depending on how abundant magic items are in your world, players may eventually want to start equipping them to their pets: ring of protection, belt of giant strength, boots of flying come to mind. You should decide if you will allow them to ( and if you will allow the beasts to attune to things) and tell them that beforehand also, so they don’t get disappointed if you say no.
All that said, you could just level them kind of like PCs. Assume their monster manual stats are level 1. When they hit level 2, they get one more hit dice of hp (a single d8 kind of thing). When they hit level 5, they get a proficiency bonus bump, etc. Maybe an ASI at 4, but I wouldn’t give them feats, just the ability score. And no extra powers or attacks, just the standard stuff, but occasionally they get a little blip when proficiency bonus goes up.
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My players LOVE adopting monsters, so far they've attempted to recruit a goblin, one player stole a Dire Wolf from a bugbear with an incredible animal handling check, and the other straight up formed a mind bond with a Grick. I've allowed them to keep their pets and they're using the standard monster stat block for their respective pets' stats.
The question I have is how would you all handle leveling monsters up, and when is the appropriate time to do so? The biggest challenge I have with this is adjusting encounters - right now they have two extra creatures on their side that skews things. I've been supplementing with just giving monsters more HP but that's not nearly as interesting as it could be. How would I factor that in? Do I treat the monsters as PCs to determine APL?
It's worth stating I'm a pretty loosey goosey DM - I want to challenge my players but I don't want to take the fun out of it. I let them do all kinds of wacky things as long as they can justify it (the one that tamed the Grick allowed themselves to gain a point of exhaustion to stay up all night and turn the Grick pink using magic), so I'd like them to keep their pets, but I don't want the encounters to become easier as a result, and I also don't want their pets becoming weaker and weaker as the campaign goes on.
Hmm. Only certain monsters can level. They are consider full party members for the encounter but they gain 1/4 of the xp. Either give them class levels. Or simply add 1 hp, +1 to hit, and +1 damage per level. When the companion gets better than the pc, the companion leaves. Why do you think the Doctor goes through some many companions.
No Gaming is Better than Bad Gaming.
One of my PC’s charmed and adopted a wolf. I don’t have the wolf level, due to it acting on instinct not experience. It gets its stat block and that’s it. There may come a time when baddies are too much of a risk for their wolf companion and the group will have to make a choice whether to risk the wolf’s life & waste health potions or release the wolf back into the wilds.
Because they are tired of almost getting killed on repeat occasions?
You say you are a loosey goosey DM, and you want your players to have "fun", and now you are seeing what the result of your actions are.
First off, monsters don't level up. Even a Paladin's Warhorse (or any Steed) does not level up, ever.
As for the action economy and encounter level problem you have created for yourself, well good luck. Not many tables exist when you have multiple monsters of varying CR levels fighting alongside the players. The smartest thing you can do is say the monsters are not smart enough to engage in combat intelligently, and don't include them in the Initiative Phase, but they are available to be hit by area effect spells. If you REALLY want to keep these monsters in the game, tell the players that for every attack the monster makes, the player forgoes an attack.
D&D for many years, many editions, have struggled with having monsters as companions, essentially NPC's. You are seeing why. BTW, if you have a Ranger Beastmaster in your group, he must be thrilled that you just blew away his special features. You really should read carefully that subclass to get a sense of how weak these companions should be.
I think you could take a look at the artificer's Iron Defender and how those gain power when the artificer levels. I wouldn't let it increase as much as that, as that's still a bit of a class feature and you don't want to make those entirely useless. Maybe swap out the mod for the iron defender (I think its int, haven't double checked) for their animal handling modifier?
God forbid players/dm's having fun playing the game, that would entirely ruin the game.
Whatever campaign you are doing, I recommend having the players either buy or hire a farm outside of their main town/city, where they can “stash” charmed creatures and put them in a protected place. This way, they can enjoy charming new beasts as their adventure continues, and you don’t have to worry about leveling something and making more work for yourself. At the end of the campaign, they can revisit the memories and their menagerie... maybe have the caretakers/janitorial staff be the charmed goblins. That way you aren’t the “bad DM” for killing wolfie.
just a thought.
Something I've seen is to have the stat boosts tied to proficiency. So when a characters' proficiency bonus goes up by one the creatures relative stats increase as well.
That said, I think it just depends on the creature. A goblin, obviously, could simply be upgraded to a full-on PC goblin, with all the stat benefits that implies. I'd start it at level 1, though, to reflect the fact that it's not as well trained as the rest of the party. Maybe it could take on the same class as whichever player originally adopted it, since I assume that's the training it would get.
The biggest problem with just letting PC pets remain with the same stats they started with is, after a certain point... they're just gonna get caught in an AOE and die. Maybe rather than worry about making their pets stronger, you should just give them some means of preventing their pets from dying outright. There was something in Critical Role where the Ranger eventually got a magic amulet that could safely house a living creature, and when that creature drops to 0 HP it immediately got teleported back into the amulet's demi-plane and became stabilized. It could either sleep off the injury for the length of a long rest or be let out after combat completed to be healed. I'm not saying you should give your party the exact same item, but something like that which makes it safer to travel with weaker companions could help preserve the fun of picking up pets without having to do a lot of rejiggering of stats to make sure they don't get killed too easily.
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I heavily prioritize my players' enjoyment over sticking with rules, because the point of it all is that it's a game. The kinds of things I allow to happen in my home game don't transfer to when I DM AL, where there needs to be an even playing field. We don't have a ranger in our party, so no, I have not robbed a player the Beastmaster trait. The reason I asked this question in the first place is so I can work WITH my players instead of against them, and still provide some semblance of a challenge so that their victories are gratifying.
Oh I like these! I'll have a closer investigation of the Iron Defender and see if I can work out a system that works, otherwise I think the proficiency bonus idea is fantastic. I definitely don't want the monsters to be as strong or stronger than the players themselves, so a 1/4 exp system would work out super well. It would probably also be worth capping how strong certain monsters could get so I don't end up with some insane lv20 Dire Wolf LOL.
Oh yeah, Vex had basically a pokeball to pull Trinket into lol. I think if it comes to that I wouldn't mind stocking a magic shop with a similar magic item. Will keep that one in the ol' back pocket of possibilities.
I really like this idea. One of my players DID express that her PC would probably obsessively collect creatures that match her aesthetic (ofc, granted she passes her checks to do so), which giving them a ranch/etc at their home base could allow for more pets, but maybe also specify that they can only bring one "combat pet" at a time, and in order to retrieve it they'd have to physically visit their home base. It'll also wonderfully complicate things once they start using teleportation to get around and they have to make decisions on which pets are worth bringing along.
I am, in general, trying to deter them from just adopting everything so I don't have a billion things to keep track of, but these are some great starting points. Thanks guys!
When they start charming a few exotic creatures have a little fun and make the farm retrofitted into an amusement park. Then you can write a home brew Jurassic Park one-shot where the charmed animals get loose. Could be a TON of fun and a great way to toss in a few fun pop Culture jokes... have the security goblin be a fat goblin named D’Nes N’dree and have him eaten by one of the escapees.
That's an incredible idea. Let the players live with the consequences of their own actions!!!
I love this! You have found something your player loves about the game, and are working with it!
One of my players wanted to adopt everything too. It started when they had to take out some ice salamander nest, and as the rest of the players smashed the eggs, he yelled, "Wait! I want one!" and he rescued it. And I was like, sure, but it's gonna be a tiny creature--you're not getting a mighty dragon thing. He didn't care.
He hatched it, it sat on his shoulder, and he'd feed it popsicles in town. It did 1 point of cold damage with its mini breath weapon. As long as it stayed on his shoulder, I never specifically targeted it (we sort of treated it like equipment in that regard).
My player wasn't looking for some crazy game breaking advantage, he just found the idea of magic pets really appealing.
It was pretty much his favorite part of the game, so I'd periodically add creatures for him to find. I eventually did the menagerie thing, where he stashed all but 1 creature per adventure, and it worked out great. Otherwise, he was just covered with little critters!
Oh, I am SO doing this! (Plus the menagerie.)
If you’re trying to level them, make sure the players understand they are getting a share of the xp, meaning the PCs level more slowly. Often, that discourages players from adopting a zoo/army. And it shouldn’t be up to you to keep track of them. If the players want pets, it’s up to the players to track them.
Also, as has been said above, you are basically giving away a class feature for free. Arguably one of the weaker class features, but still a class feature. It will make encounters easier for the players. You might want to find a way to force them to invest some kind of resources into them to balance it out.
By RAW, they are not PCs and therefore shouldn’t get death saves, 0hp = dead. You should decide if you are going to follow that or not and be sure to tell the players either way. And depending on how abundant magic items are in your world, players may eventually want to start equipping them to their pets: ring of protection, belt of giant strength, boots of flying come to mind. You should decide if you will allow them to ( and if you will allow the beasts to attune to things) and tell them that beforehand also, so they don’t get disappointed if you say no.
All that said, you could just level them kind of like PCs. Assume their monster manual stats are level 1. When they hit level 2, they get one more hit dice of hp (a single d8 kind of thing). When they hit level 5, they get a proficiency bonus bump, etc. Maybe an ASI at 4, but I wouldn’t give them feats, just the ability score. And no extra powers or attacks, just the standard stuff, but occasionally they get a little blip when proficiency bonus goes up.