Grass:
Move the ice crystals to spawn in the grass biome.
Reskin them to look like tombstones.
Make hostile bots spawn in the biome that look like zombies.
Snow:
Reskin the Snow Piles as dead trees and increase their spawn count.
Reskin the yetis as normal wendigos.
Reskin the Yeti boss as a Wendigo King that shoots out a different projectile.
Lava:
Reskin the Roku as a Demon
Maybe reskin the Chimeras as ghosts.
Obstacles
TOMBSTONES
They would be reskinned Ice Crystals that are in the grass biome.
PUMPKINS
These would be reskinned rocks (optional: have them spawn only in the grass biome.)
DEAD TREES
These would be reskinned versions of the snow piles.
Mobs
Zombie
These spawn in the grass biome and are hostile to players and bots.
Wendigo
These are reskinned yetis.
Wendingo King
This is a reskinned Yeti boss, make it a little more detailed than the normal Wendigos because having them the same would be boring.
Ghost
These are reskinned chimeras.
King Ghost
Reskinned Roku
OTHER THINGS
SKIN UPDATE!!! (priority to Halloween or fall-related skins.)
V1 Skin Sale: 2nd Zombie skin, Pumpkin, and other Halloween-related skins
Evolution update with tier 3 evolutions (recommend releasing them in 2 parts, adding 4 first, then adding the remaining 4.)