While we are getting a couple of new ones, the vast majority of the main mechanics are ones that weve seen before
Darkness is a fun one -- the spell effect does have the idea of sudden darkness happening in the midst of combat (hence creatures still being 'tapped') and causing all the attackers to miss their mark (hence no damage is dealt)
While the deck has some issues, conflicting themes arent one, as this deck is pretty conciseit has a few outliers, but not at a systematic level
It increases the Exp
Sacrifice those tokens at end of combat. The real stinger, though, is the final part, which reads: Whenever Shredder deals combat damage to a player, that player loses half their life, rounded up. The idea is that your Shredder, or its clones, will do damage to an opponent and halve their life total - but if you get Bloodletter of Aclazotz on the field, you can finish them