Flying When Skyline Savior enters the battlefield, return a permanent you control to its owner's hand. If it's a non-Angel creature card, it perpetually gets +1/+1, gains flying, and becomes an Angel in addition to its other types.
Flying At the beginning of combat on your turn, you may pay {G}{U}. When you do, put a +1/+1 counter on another target creature you control, and that creature gains flying until end of turn.
Flying Whenever Skyship Plunderer deals combat damage to a player, for each kind of counter on target permanent or player, give that permanent or player another counter of that kind.
Whenever equipped creature attacks, you may return a land you control to its owner's hand. If you do, the creature gets +2/+2 until end of turn. Equip {2}
Whenever Slagstone Refinery or another nontoken artifact you control is put into a graveyard from the battlefield or is put into exile from the battlefield, create a tapped Powerstone token.