Is like mantis or like oversized bugs may be also available????
No, it is only available in the demo version only big-golem & manties is only available in version 0.2 & 0.2.1, the replacement for big-golem is papa goblin LAGS said in this devlogs
but looking at the pictures gallery in version 0.7.1.2 there are lots of possibilities that might exist in the future, such as mumies, demons, papa goblins, shell worms, jellyfish, red jelly, and slime for the Hailey game. I don't know if that will come true or not but I hope it's true