This question arose at my LGS during Commander game.
If Wasitora, Nekoru Queen deals combat damage to a player that is enough to kill him (assuming there are other players still alive), will its trigger still cause controller to put 3/3 Cat? I am a bit confused about checking wether dead player can sacrifice creature or not.
I looked through rules 603, 608 and chapter 8 in CR, and found nothing relating to this case.
My basic understanding is that the game still can track that player could not sacrifice a creature (even though player is not in game when this check appears), and dragon's controller gets a token, but I would like to know what rules explain that interaction.
Thank you kindly.

Edited Bohdan Yarema (Sept. 20, 2017 09:06:50 PM)

If Wasitora deals combat damage to a player, and that player has left the game by the time the trigger resolves, that player isn't able to sacrifice a creature (being gone and all), so Wasitora's controller gets a token.

There isn't a specific rule to cite for this, for the same reason there isn't a specific rule to cite for the fact that Wasitora's controller will get a token if the player it hit is still in the game but doesn't control any creatures to sacrifice, or does have creatures but one of them's a Sigarda, Host of Herons. The ability says what happens if the player doesn't sacrifice a creature, so that's what happens, regardless of the reason why the player was unable to do so.