Skeletons and Zombies you control get +1/+1 and have menace.
Whenever you commit a crime, create two tapped 2/2 blue and black Zombie Rogue creature tokens. This ability triggers only once each turn. (Targeting opponents, anything they control, and/or cards in their graveyards is a crime.)
Gisa anchors a mono-black Zombie/Skeleton tribal deck that pumps your whole undead army with +1/+1 and menace while spitting out 2/2 Zombie Rogues every time you commit a crime. You commit crimes naturally—removal, edicts, graveyard hate, drain spells—so you build a wide, evasive board and crash in for lethal. Early turns develop ramp and small zombies; mid-game you snowball tokens off your interaction and finish with anthems or aristocrats drain.
Crimes are trivially easy in black, so the token engine fires nearly every turn for free value
Anthem + menace makes your whole board hard to profitably block
Mono-color consistency: clean mana, easy access to powerful black staples
Synergizes with both go-wide tokens and aristocrats sacrifice strategies
Board wipes hit your token-heavy strategy especially hard
Ward and pump only protect Gisa herself; the deck leans heavily on her staying out
No card advantage built into the commander beyond bodies
Vulnerable to graveyard hate slowing reanimation/recursion subthemes
Adds a parallel zombie token engine and card draw that stacks with Gisa's board.
Tighten the crime triggers by running cheap, repeatable interaction (edicts, pingers, graveyard-targeting spells) so the token engine fires every turn. Add a true sacrifice + aristocrats package (Viscera Seer, Blood Artist, Pitiless Plunderer, Dictate of Erebos) plus token doublers like Anointed Procession to convert the board into inevitable drain. Top-end ramp—Cabal Coffers/Urborg, Nykthos, Black Market—lets you close with Gray Merchant or a big Torment of Hailfire.