If I cheat in {Scourge of the Throne} using {Kaalia of the Vast} will Scourge's ability trigger?
No, the ability won't trigger. "Attacks" means it is declared as an attacker on its own. Kaalia puts it into play tapped and attacking, so it is never declared as an attacker. Hope this helps :)
Cool thanks
This is basicly the same thing that happens with {Preeminent Captain} and {Brimaz, King of Oreskos}, so no kitty from brimaz for that fight.
I had the same issue with Kaalia and {Aurelia, the Warleader}. Best thing to do is hard-cast them first, then attack to start combat-accelerating creatures.