Aveline de Grandpré

A disguise ability lets you cast a card face down by paying {3} and announcing that you are using a disguise ability. Any time you have priority, you can turn a face-down permanent you control face up by paying its disguise cost.

You must ensure that your face-down spells and permanents can be easily differentiated from each other. You’re not allowed to mix up the cards that represent them on the battlefield to confuse other players. The order in which they entered the battlefield should remain clear, as well as what ability caused them to be face down. (This includes disguise, cloak, and in games involving older cards, morph and manifest, as well as a few other effects that turn cards face down.) Common methods for doing this include using markers or dice, or simply placing them in order on the battlefield.

If a creature you control with deathtouch deals combat damage to a player at the same time it’s dealt lethal damage (perhaps because it has trample and was blocked), it will die before Aveline’s triggered ability resolves and puts +1/+1 counters on it.