Sacrificing 6+ power creatures to draw 6 cards and discard 3 lands is powerful
While your decks are important, all those cards you keep tucked away in storage also need some love
Skill Drain is perfect for Control decks that primarily run backrow and little Monsters, as losing their Monster effects will hardly matter
Additionally, the tribe uniquely has access to not one, but two cards that allow a player to break the singleton rule of commander, as a deck can contain any number of copies of Rat Colony and Relentless Rats respectively, allowing for very consistent builds
Mage Wars came out last year
And if your opponent manages to kill your Relinquished and your Gravity Bind, you can summon Divine Serpent as your backup, another monster that is hard to deal with