I'm working on a one shot that will take place in a lizardfolk temple in a heavy jungle and I need some advice on:

1. What rooms should the temple have (i.e. hatching rooms, nurseries, etc.)

2. What kind of traps would be appropriate for a lizardfolk temple

3. What monstrous working animals/mounts would lizardfolk use

I wouldn’t think a “Temple” would have hatching rooms or nurseries. A “Temple Complex” May have those things, but they would probably be separate from the temple proper. A temple would have a main worship area, a sepulcher, the leader’s sanctum (office) stuff like that.

Possibly also smaller "dormitory" rooms for the acolytes.

And a treasury for all of the offerings.

Perhaps also a small prison for the offerings that don't come in the form of material wealth. Right next to the altar, of course, for swift transportation when they feel the need to have a sacrifice.

 1. What rooms should the temple have (i.e. hatching rooms, nurseries, etc.)

Knave / Altar, worship area, entry foyer - honestly temples on their own aren't that complex or exciting. You could add a rectory or barracks for priests and guards. Who is using the temple? Is there a local lizard-folk village, or is this a holy site where lizard-folk pilgrimage to and/or live? In the case of the latter, you would have monastery quarters, gardens, pens for food animals ( and/or living sacrifices - could even be prison cells for the later if humanoid sacrifice is on the agenda ), extended dormitories for a larger workforce needed to maintain the complex. How do the lizard-folk worship? Are there offerings? Are they stored in a vault? It it's a large complex, you can pretty much merge anything you'd find in a small/medium village into the complex: blacksmith, armory ( for the Temple Guards who now double as local police/militia), tannery, bakery,  hatching rooms, nurseries, etc. It all depends on who using the temple, where they live, and what activities is the temple ( complex ) used for.

2. What kind of traps would be appropriate for a lizardfolk temple

It's in a jungle, so I'd veer toward Punji stick traps, trip wires/vines attached to dead-falls, and the like: things you could build out of local jungle materials easily. In the temple itself, divine magic might be used to create more sophisticated magical traps.

Remember, traps have a purpose: area denial ( no one should go in there ), or security device ( people go in/through here, but they must be able to bypass the trap ). Traps also have one or more methods: kill, render unconscious, trigger an alarm, destroy something valuable rather than let someone steal it, etc. Trap bypasses are going to be: things you know ( step only on these particular cobblestones ), things you are ( the glyph explodes when a non-lizardman approaches it ), or things you have ( those wearing an amulet of a priest can pass through the archway into the treasury unharmed, everyone else suffers 1d12 lightning from the arcane discharge of electricity, trap has a 1 in 6 change of recharging for every minute that passes after it is set off ).

3. What monstrous working animals/mounts would lizardfolk use

Giant Lizard s seem to be a good bet here. They're specifically called out as draft animals for Lizardfolk. Since they have a climbing speed, I think that could make for some interesting mounted combat options. Perhaps the Temple guard has specially trained war-lizards which they can ride up the trees and over the canopy, giving a jungle combat encounter with them an interesting 3rd dimension. Or the riders could dismount and have their war-lizards fight alongside of them. I'd bump up the stats for a "war lizard" :)

Quote from IamSposta >>

I wouldn’t think a “Temple” would have hatching rooms or nurseries. A “Temple Complex” May have those things, but they would probably be separate from the temple proper. A temple would have a main worship area, a sepulcher, the leader’s sanctum (office) stuff like that.

 I think a Lizardfolk temple would actually have a lot of utilitarian details. I think of Lizardfolk as generally pretty practical-minded... their description in Volo's focuses a lot on their lizard-brain way of thinking... they don't care much for symbolism or art and they tend to speak very plainly and literally with practically no flavor or metaphor. If a Lizardfolk says, "I could eat a horse", it's because they see a horse and intend to eat it. If Lizardfolk are building a temple it's most likely a transactional thing... they're aware that a being of some power will grant them a gift or blessing if treated with reverence, so they build a temple facilitate that reverence. But at the same time, if they're putting in all the effort of building a great big stone building somewhere (or whatever it's made out of), I'd imagine that they would also find practical uses for it in addition to its function as a temple. Hatching rooms and Nurseries particularly make sense to me, the logic being, "The being we worship pays attention the most to this building, so let's put our eggs and hatchlings in here so the being will help protect them when we're busy hunting."

I would think hatching rooms and such to be essential to a temple. The eggs incubating  in the holy water, or steam, or mud, of the temple ensure healthy babies or a special breed of lizard.

Depending on which god the temple is dedicated to they could be raising them from birth to fill a certain caste role.

The only absolutely required element of a temple is a ritual area, everything else depends on how the temple is used and the details of the religion

• The priests/acolytes need to live somewhere. This is probably either the temple, or the community that the temple serves. It's possible that temple is in the middle of a community, a community lives inside the temple, or that the temple and the community overlap.
• Ritual objects and supplies need to be stored somewhere. Again, temple or community.
• Sacrifices (might be objects, plants, beasts, humanoids, ...), if an issue in the religion, need to be stored somewhere. It's possible that the sacrificial ritual involves eating the sacrifice, in which case it's likely that some part of the ritual area can double as a feast hall.
• Hatching rooms, nurseries, etc, are more features of a community than a temple (and may or may not be communal), but of course the temple might serve a community purpose.

In terms of the other two questions, dangerous (non-warning) traps in areas people need to regularly pass through are not particularly realistic, unless the traps are harmless to the natives, but on the other hand, this is D&D, so realism doesn't have to enter into it; I suggest Indiana Jones or Tomb Raider as possible inspiration. For beasts, giant lizards are possible, or you might go whole hog and toss in dinosaurs.

Quote from Pantagruel666 >>

 

In terms of the other two questions, dangerous (non-warning) traps in areas people need to regularly pass through are not particularly realistic, unless the traps are harmless to the natives, but on the other hand, this is D&D, so realism doesn't have to enter into it;

 Since they have a swim speed and can hold their breath for an extended period of time, I'd go with long murky waterways. Just a regular thing for lizardfolk but humans risk drowning.