Ascending Aven is a common Creature — Bird Soldier card from Onslaught (ONS), collector number 68. Current market price: $0.04 (foil $0.55), TCGplayer market prices via Scryfall.
Flying This creature can block only creatures with flying. Morph {2}{U} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)