Serpent-Blade Assailant

Deathtouch on loan is a nastier gift than a static keyword because it warps a single combat step and then evaporates, leaving the durable payoff behind. The permanent +1/+1 counter is what stays; the granted deathtouch is a one-turn threat that forces every blocker into a losing trade. Point the trigger at your best attacker and you get a lasting stat bump plus a turn where any block trades up for you; keep it here and you have a 3/2 deathtoucher, a clean floor that means the trigger is never wasted. The choice is real, which is what separates this kind of design from a free upgrade. The caveat the design does not soften is delivery: the enters-the-battlefield trigger is targeted, so it goes on the stack pointing at a creature, and if that creature is removed in response the whole trigger fizzles and the counter is lost. The self-target fallback only protects you from having no legal target at all; it does not make the ability immune to interaction once you have aimed it elsewhere. That gap between a durable counter and a fragile, trick-like delivery is the tension the mechanic is built around, and it shows up in sharpest form when the loaned keyword is deathtouch: a granted ability whose entire value lives inside one combat, gone the moment the turn ends.