Scheming Fence

Where earlier "steal an activated ability" designs handed you the ability wholesale, this one takes and gives in the same breath: it shuts off the chosen permanent's activated abilities entirely, then grafts them onto a 2/3 body and pays the color tax for you by letting any mana fund them. That double clause is the whole strategic axis. The shutdown is total, covering loyalty abilities too: point it at a planeswalker and that walker can no longer activate anything, though the Fence itself inherits only the walker's non-loyalty abilities (loyalty is carved out of what it gains, not out of what it locks). Because it is a replacement effect keyed to the creature entering, the choice locks in as it arrives, neutralizing a mana rock, a pinger, an opposing creature's tap-to-do-anything, or an equipment's activation while handing you the reins. The mana-of-any-color rider does more than it looks: inherited abilities often carry off-color costs, and a two-color creature firing a five-color permanent's ability without fixing is the design compensating for the fact that borrowed abilities rarely fit your manabase. It answers exactly one permanent, chosen once with no re-target, so it lives or dies by what was on the board when it entered: a lock that snapshots the moment it arrives rather than a repeatable threat. A taxer and a thief folded into a single creature, priced as a body first and a lock second, rewarding a read of the opponent's board over a build around your own.