One of the biomes in this dimension is the Frostfertile Jungle, despite the harsh cold temperatures, there are still some plants growing. These plants were placed here by the people of the Ancient cities and evolved to survive the cold. These plants in which are called Frostfertile. Frostfertile are a tree-like plant that has different ice varients for its leaves, and requires liquid nitrogen or nitrogen crystals to grow faster. And there are frozen lakes of nitrogen crystals that the Frostfertile can grow from.

Ice Crab

Ice Crabs are neutral crustacean mob that spawn in frostfertile jungles and aurora paradise, they attack by pinching and launching an icicle at you from a hole in its snowy back, they can drop packed ice, blue ice, snowballs, and cryothite shards (rare). The icicle can grow if fed sugar ice (can be found in frostfertile) or swimming in nitrogen. Although it is neutral, it becomes hostile if you get too close to it, but it can be tamed with the same thing you feed it, it doesn't spawn a baby ice crab but instead spawns an egg and stays near it to protect it.

Frostfertile

Frostfertile is a tree-like plant that can thrive in cold biomes and grow with nitrogen, instead of needing a sapling to grow from, you can just place down a frostfertile stem and use nitrogen crystals on it to grow a frostfertile tree. They don't have leaves, but they do have sugar ice, which can be used to tame or breed ice crabs. If put in a furnace, you will get sugar (of course), and that's it.