Thraximundar

The attack trigger is a tax that offers nothing back: the defending player chooses what to give up, which means they hand you their worst creature, but they hand you a +1/+1 counter for the privilege anyway. That second clause is the part that turns a beater into a centerpiece, because it doesn't care whose sacrifice it is. Every Diabolic Edict, every sacrifice outlet, every aristocrat engine on either side of the table feeds it. The card was built to anchor a Grixis shell that wanted to grind the board down to nothing and grow a clock while doing it: forced sacrifice on the attack step strips a blocker before damage, the counter rewards the sacrifice, and haste means a freshly cast 6/6 starts taxing the turn it lands rather than waiting to be answered. The design tension is that a player reduced to a single creature is forced to give it up, so the attack trigger is at its sharpest exactly when it is least answerable, and at its dullest against a wide board it can only chip at all day. It reads as a top-end finisher and plays as an attrition piece, and that gap is what dictates how the whole deck around it gets built: you want forced-sacrifice effects and your own sac fodder so the counter clause keeps ticking even on turns Thraximundar isn't swinging.