Here are some conformed future features!
creatures:
swordfish
giant seahorse
umbrafish
Kracken
Aquatilium flower
hatzegopteryx
helicoprion
kronosaurus
Items:
air sack
diving gear(armor set)
fishing spear
Locations:
open ocean
abyss ravine
coral reef
deadly swamp
hatzegopteryx spires
Ice flow
refuge island
Resources:
driftwood
blubber
oysters
pillar coral
Seaweed
pure coral
Structures/vehicles:
Wooden pontoon foundation
fish trap
TEK submarine
metal pontoon foundation
TEK pontoon foundation
canoe/skiff
submarine
Coral building set