Rathi Trapper

A recurring tapper has always been a soft form of removal, and folding that effect onto a 1/2 for two mana puts it where it belongs. Black is the color that kills creatures, so an effect that subtracts one from combat reads as native rather than imported here, even though tapping permanents was historically a blue or artifact trick (Icy Manipulator did the same work for four mana and four to activate). The black mana payment on top of the tap is the throttle: a two-drop that could freeze anything for free every turn would warp board states, but making each activation compete with your other plays for mana keeps it repeatable without being gratuitous. Because the ability fires at instant speed, the real value lands on the opponent's turn: freezing an attacker before it can swing, or pinning a blocker so your own creature connects. The Rebel typing extends the reach, since the cards that fetch Rebels onto the battlefield turn a singleton tapper into something you can find and rebuy without ever drawing it. As an engine piece it does quiet, grinding work: it never kills anything outright, but turn after turn it removes a creature from the math, which over a long game is most of what removal accomplishes anyway.