#bloodedknight

In general, pretty poorly.

Shirei’s trigger looks at the creature’s power as it last existed on the battlefield, which includes the +1/-1 from Skullclamp. So that 1/1 creature you just Skullclamped died as a 2/0 and won’t trigger Shirei. You’ll need to be Skullclamping 0/1′s to get any extra value from Shirei.

Only the controller. In a change from previous rules, creatures now attack a specific player instead of the whole team, so only creatures that attack the player with Propaganda are subject to its cost to attack.