Thieving Skydiver

Steal effects on creatures are old news; Threaten walked so a hundred temporary-Control-Magic bodies could run. What sets this apart is theft that is permanent, scalable, and airborne, all bolted onto a body you were happy to run anyway. Unkicked, it is a two-mana 2/1 flier: a fine tempo creature that costs you nothing to leave the toolbox open. Kicked, the X you pour in sets the ceiling on what you can strip off the other side of the table, and the range is deliberately wide: a Signet or a Sol Ring one turn, an equipped Sword the next. The Equipment clause is the part that turns a good rate into a beating: rip a Sword off its wielder and it snaps onto the Skydiver itself, so you gain the artifact and immediately hand your evasive body a weapon it never had to pay to equip. The whole thing hinges on the enters trigger, which means the artifact you want has to be on the battlefield when the Merfolk lands, rewarding you for holding the card until the target reveals itself rather than deploying on curve. That patience, the willingness to sit on a two-drop for several turns until the right piece of hardware exists, is the axis the design is built around, and the flying keeps the whole operation relevant even when there is nothing worth stealing.