Flying (This creature can't be blocked except by creatures with flying or reach.)
When Aegis Angel enters the battlefield, another target permanent gains indestructible for as long as you control Aegis Angel. (Effects that say "destroy" don't destroy it. A creature with indestructible can't be destroyed by damage.)
If another player gains control of Aegis Angel, the permanent will no longer have indestructible, even if you regain control of Aegis Angel.
If Aegis Angel leaves the battlefield, you no longer control it.
If Aegis Angel and the permanent would be destroyed simultaneously, only Aegis Angel will be destroyed.