You can build on its back without a saddle, however IF YOU EQUIP A SADDLE YOU WILL LOSE EVERYTHING. If you cryo you will also LOSE EVERYTHING regardless of saddle or not. Vote for more people to see

-AK

They apparently have some sort of gravity field on them allowing players to walk on its back while submerged

You can use hlna to teleport you and your turtle anywhere (they can walk on land) but can only breed under water.

Tamed you'll be able to build on its back. When diving he provides an oxygen bubble on his back allowing you to submerge your base on the floor of the ocean.

Are you turtley enough for the turtle club?

It does NOT irrigate crop plots on its back or in a building.

Crop plots built on the shell are automatically irrigated. No need for pipes!

Probably the best platform dino to live on, the megachelon can fit a 5 by 7 of foundations on its shell, and many structures, like chemistry benches, grinders, and even industrial forges can be built on it while staying there when underwater. You don't even need scuba gear when going underwater, staying above one provides oxygen. Not only this, but they actually have surprisingly good melee damage, as well as being one of, if not the best fiber harvester in the game. Different resources will constantly build up in its inventory, including rare mushrooms and flowers. They also automatically irrigate any crops placed of them. Get an imprinted one for extra speed, damage, and resistance, then give it an good armor saddle from the frog escort mission in the bog, and you have an extremely tanky resource gathering portable base, war machine, greenhouse, and water exploration mount!

Controls for play station (just to be helpful):

R2: attack

L2: bubble attack

Right stick (push): dive

Left stick (push): N/A

/\: dismount

[]: their inventory

O: your inventory

X: quick ascend/ surface

Movement controls other than dive and surface are regular

-Sarco Master 🐊

Do not ever throw this out with cryosickness. It takes legit 10+ hours to wake back up. Craziest thing ever. Lol