Falthis, Shadowcat Familiar
The whole card lives in that first line, and the trick is that it upgrades every commander you control, itself included. Menace and deathtouch is one of the tightest combat-math pairings in the game: menace forces the double block, and deathtouch punishes it, since a deathtouch attacker only needs to assign one point to each of the two bodies it drags into combat. Attach that to a fragile 2/2 for and you have a modest voltron threat; attach it via Partner to a second commander and the second commander is the one that suddenly can't be chump-blocked by a single creature and can't be gang-blocked profitably. That reframes the design as a support piece rather than a lead. You are rarely casting this to swing with the 2/2. You are casting it so your other legendary connects through walls, so a voltron general's commander damage lands on contact, so any partner's attack becomes a lethal, awkward-to-answer proposition. The keyword grant is a tax paid once from the command zone and applied to every attacker you can call a commander. As a Nightmare Cat it also gestures at a cat-tribal identity, but the mechanical weight is entirely in that command-zone math: a two-keyword upgrade that scales with whatever it stands beside, and quietly makes itself more dangerous than a 2/2 has any right to be while it's at it.


