Nemesis

Nemesis is an NPC-Hostile kind of creature, created by different outbreaks or conflicts, It is persistent, and has a complex mind, based on events.

Corruption Nemesis
Created by Corruption Outbreak, this trickster can either lead a devouring swarm or a hivemind working together. Possible to create a small civilization, it evolves along your progression, and can only be defeated only if you develop fast enough, creating a Rivalry Situation. The Corruption Nemesis is a hivemind on the next level, created from artifical evolution. Try not to give this enemy a chance to strike because... well... uh...

Crimson Nemesis
Created by Crimson Outbreak, this mighty warrior leads a pack or an army of intelligent but extremely brutal hunters. Possible to create a civilization, the Horde evolves along your progression, and can be defeated early if you trick them, but beware, they possibly could trick you too! The Crimson Nemesis is a result of an experiment going wrong, giving intelligence to something that shouldn't have it.

Hallow Nemesis
Created by angering the Hallow. This holy creature leads a crusade against infidels, or basically it destroys whatever destroys the Hallow or torture it's inhabitants. It is always the same creature, an ancient Paladin Spirit. The Hallow Nemesis creates a complex civilization that progresses alongside you. It is extremely intelligent and able to create complex armies of Hallowed hostile monsters, such as an aerial Pixie Squadron or a land Knight platoon, you need all your brain power used on tactics to defeat this complex enemy. This commander also thinks, it can possibly siege your little town you made.