Veteran Survivor

Survival — At the beginning of your second main phase, if this creature is tapped, put a flying, lifelink, or +1/+1 counter on it.

Whenever this creature or another creature you control dies, if it had counters on it, put those counters on up to one target creature.

Survival — At the beginning of your second main phase, if Improvising Aerialist is tapped, Improvising Aerialist and the top creature card in your library without flying perpetually gain flying.

Survival — At the beginning of your second main phase, if this creature is tapped, put a flying counter on it. This ability triggers only once.

Vigilance

Threshold — As long as there are seven or more cards in your graveyard, this creature gets +1/+1 and has flying.

Whenever this creature enters or attacks, exile up to one target card from a graveyard.

Coven — : Choose a color. This creature gains hexproof from that color until end of turn and can't be blocked by creatures of that color this turn. Activate only if you control three or more creatures with different powers.

Threshold — This creature has flying as long as there are seven or more cards in your graveyard.