The Yeerk, in all honesty, amounts to little more than a pale, slug-like parasite...however, this "parasite" has an extraordinary evolutionary advantage.
By narrowing itself and slipping into a creature's earlobe (or however to reach a brain), a Yeerk is capable of taking complete control of that creature - physically and mentally.
The weakness of the Yeerk is that they require to be subject to Kandrona radiation at least once every three days. This has become less of an issue in recent times with the invention of portable Kandrona radiators, which almost every Yeerk has access to.
For a long time, Yeerks worked as a solitary group - unaffiliated with the main actors of the galaxy. During the last war between the UGA/HF and the Black Horde, the Yeerks threw themselves in with the Black Horde and made fantastic spies for BH operations.
After the Black Horde was defeated and left in shambles, the Yeerks were one of the main players (just behind the Dark Elves) that started to rebuild the once formidable faction.
- Controller: The character starts with a host body of the player's chose. In the end, this is left up to the DM to allow (some races are not available to be Controllers).
- Requires Kandrona radiation for at least one hour every 3 days. The character starts with portable Kandrona Radiation Generator.