I'm level 3 and what is this. 

So what good would attacking a tendril do, if the Roper can just replace it for free? Does it take an action to replace the tendril? Or would attacking the tendril be purely for releasing whoever is grappled?

Quote from DruTheBear >>

So what good would attacking a tendril do, if the Roper can just replace it for free? Does it take an action to replace the tendril? Or would attacking the tendril be purely for releasing whoever is grappled?

BINGO

When you’re restrained all your attacks are made at disadvantage.

Say your party is fighting a roper, it’s your turn - the party member whose turn is next is currently wrapped up in a tendril, you’re free. If you chose to destroy the tendril instead of attacking the roper your friend is freed, allowing them to take their attacks at a normal roll, instead of at disadvantage.  

Fireball, nukes the arms, it regains 1 per turn free but still becomes basically a sponge at that point. 

DMs, play your ropers as stalactites instead of stalagmites. Attack from high above--up to 50 feet away, then pull the grappled and restrained victim up to the roper hanging from the cave ceiling. Even if they break free, they are going to take damage from the fall. And even if they don't the roper can always just let them go.

I can see a Roper hunting in that way if its' prey is especially tough.

Drop them on the floor and let their own weight break them..easy chewing then.

We need 5E stats for the foulest of Ropers: Urophions

Quote from Glandor >>

I can see a Roper hunting in that way if its' prey is especially tough.

Drop them on the floor and let their own weight break them..easy chewing then.

 Remember, ropers have an intelligence of 7. They aren’t just unintelligent predators, so this wouldn’t just be a useful hunting strategy, it would probably be a no brainer for them.

Quote from Yeetlord300 >>

Quote from Glandor >>

I can see a Roper hunting in that way if its' prey is especially tough.

Drop them on the floor and let their own weight break them..easy chewing then.

 Remember, ropers have an intelligence of 7. They aren’t just unintelligent predators, so this wouldn’t just be a useful hunting strategy, it would probably be a no brainer for them.

Ropers have frighteningly high Intelligence scores.

It’s as smart as an orc.  Noticeably smarter than a ogre.  There are PCs with 7 Intelligence.

I'm gonna have to nerf this. 20 Natural AC? Insane!

I think I would nerf its health, and as that its fleshy interior is just really weak

Quote from Dr_Frederick >>

Quote from Yeetlord300 >>

Quote from Glandor >>

I can see a Roper hunting in that way if its' prey is especially tough.

Drop them on the floor and let their own weight break them..easy chewing then.

 Remember, ropers have an intelligence of 7. They aren’t just unintelligent predators, so this wouldn’t just be a useful hunting strategy, it would probably be a no brainer for them.

 

Ropers have frighteningly high Intelligence scores.

It’s as smart as an orc.  Noticeably smarter than a ogre.  There are PCs with 7 Intelligence.

 Lol my barbarians intelligence is only 6

If a 5-level fighter takes their turn before the roper and action surges to roll 4 attacks and one bonus attack from something like GWM against the Roper, the creature attacks only two times instead of five. He can repeat attacks in the next turn to rid him of all tendrils, then use one attack on each subsequent turn to counter the re-growing tendril and the other to attack the creature itself.

It renders the Roper's ability to control the battle nearly non-existent and leaves them only with its bite. If noone attacks the tendrils, he should keep characters away or restrained forcing them to waste actions and attacks on its tentacles.

I’m scared I may have missed my chance to annoy my players with a bunch of really cool and annoying monsters. This is a cool thing, but not at level 11... right?

It's never too late. Modify it as needed or place it with other threats to be a variable they can't ignore but can address either.

Quote from ClericalKenku >>

I’m scared I may have missed my chance to annoy my players with a bunch of really cool and annoying monsters. This is a cool thing, but not at level 11... right?

 It's never too late. Modify it as needed or place it with other threats to be a variable they can't ignore but can address either.

That's ignoring most of the other factors that are at play during the encounter. First, the Roper has a 20 AC, so even with maxed STR/DEX you'd still need to roll at least a 12 at level 5 to even make an attack land (GWM is not your ally in this scenario, you wouldn't even get the bonus action attack since the tendril isn't a separate creature). Second, each tendril has a range of 50 ft, meaning that it's getting you the party quicker than the party is getting to it in most instances. Third, you never notice a Roper until it's too late due to its false appearance ability. Finally, it also has spider climb; there's nothing stopping it from just hanging on ceiling keeping out of range of martial combat all together.

a raven has an int score of 2 and ravens are known to get very creative with their food. crows too, crows in japan put walnuts at traffic stops during a red light, wait for cars to run over the shells then eat the nuts. 

These things aren't immune to being shove prone hmm, though they are strong and impose disadvantage on strength checks with their tentacles, so succeeding in shoving them over would be a challenge. I'm spitballing here, but if you have no other options, a raging Barbarian or enlarged Fighter with athletics prof could shove it over and grapple it, giving it disadvantage on all its attack and everyone advantage to hit it, or cancelling the disadvantage on roped folks. This will only cancel the advantage on its bites if you're roped, but it'll make it harder for it to re-rope people too. For it to even get up and flip things back, it would have to use an action to escape the grapple, wasting a turn. It's... not the best way to deal with a roper, but if you don't have any better alternatives, it can make it a lot easier to handle.