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{T}, Sacrifice Flight Spellbomb: Target creature gains flying until end of turn.
When Flight Spellbomb is put into a graveyard from the battlefield, you may pay {U}. If you do, draw a card.
For flying to work as an evasion ability, an attacking creature must be granted flying before the declare blockers step begins. Once an attacking creature has become blocked, giving it flying won’t change that.
