Sidewinder Sliver

Flanking is a combat keyword that lives entirely on offense: when a creature without flanking blocks one of your attackers, that blocker shrinks by -1/-1 before damage, often dying to a Sliver it was meant to trade with. Granting it to the whole tribe makes an aggressive Sliver curve genuinely punishing to stall. Throw a token or a freshly cast blocker in front of an attacking Sliver and it withers before combat resolves; the defender loses a creature just to chump while your attacker walks away. For a deck whose individual threats are small, that is the pressure that breaks a board clogged with blockers. The body is incidental; what one mana buys is a standing tax on your opponent's blocking decisions. And flanking compounds where most keywords do not: flying, trample, and lifelink are binary, present or absent, but flanking stacks, so two sources hit a blocker for -2/-2, three for -3/-3. Add a couple of these grants alongside another flanking source and an attacking Sliver can erase whatever stands in front of it outright. That stacking is the quiet reason a keyword-granting lord scales harder than a flat power boost: the penalty grows with the number of flanking effects on the board, not with the size of any one creature.