Ascend (If you control ten or more permanents, you get the city's blessing for the rest of the game.)
All creatures get -2/-2 until end of turn. If you have the city's blessing, instead only creatures your opponents control get -2/-2 until end of turn.
1/19/2018 Golden Demise affects only creatures that are on the battlefield at the time it resolves. Creatures that enter the battlefield later in the turn won’t get -2/-2. Similarly, if you have the city’s blessing, creatures that come under your opponents’ control later in the turn won’t get -2/-2.
1/19/2018 Once you have the city’s blessing, you have it for the rest of the game, even if you lose control of some or all of your permanents. The city’s blessing isn’t a permanent itself and can’t be removed by any effect.
1/19/2018 A permanent is any object on the battlefield, including tokens and lands. Spells and emblems aren’t permanents.
1/19/2018 If you cast a spell with ascend, you don’t get the city’s blessing until it resolves. Players may respond to that spell by trying to change whether you get the city’s blessing.
1/19/2018 If you control ten permanents but don’t control a permanent or resolving spell with ascend, you don’t get the city’s blessing. For example, if you control ten permanents, lose control of one, then cast Golden Demise, you won’t have the city’s blessing and the spell will affect creatures you control.
1/19/2018 If your tenth permanent enters the battlefield and then a permanent leaves the battlefield immediately afterwards (most likely due to the “Legend Rule” or due to being a creature with 0 toughness), you get the city’s blessing before it leaves the battlefield.