If I play Sacrifice on a unit targeted by Stupefy, will Stupefy still draw a card?

To determine what happens, we must look at how costs are paid and how targeting works in Riftbound.

The Ruling

Yes, you will still draw the card.

According to RiftJudge FAQ #9506 and Rule 359.3.e.6, if a spell has multiple instructions and some targets become illegal (or the unit is removed from the board) after the spell is on the chain, the spell will still resolve and execute any instructions that do not require the illegal target.

The Sequence of Events

1. Playing Sacrifice: When you play Sacrifice, you must pay its costs (1 Energy and killing a friendly Mighty unit) before the card is added to the chain.
2. Chain State: By the time you have priority to play Stupefy in response to your opponent's play, the Sacrifice is already on the chain and the unit has already been moved to the trash to pay the cost.
3. Targeting Stupefy: If you played Stupefy earlier (when you had focus in an Open State) targeting a unit, and your opponent then plays Sacrifice using that same unit as the cost to pay for it, the unit is sent to the trash before Stupefy resolves.
4. Resolution: When Stupefy resolves:
   • The instruction to "Give a unit -1 might" fails because the unit is no longer on the battlefield (it is an illegal target). Per Rule 359.3.e.6, this instruction is ignored.
   • The instruction to "Draw 1" does not require a target and is not dependent on the first instruction. Therefore, it still executes.

As clarified in RiftJudge FAQ #669 and #9506, a spell resolves even if some or all of its targets become illegal; you simply skip the instructions that cannot be performed and proceed with the rest.