Well if you want spell ideas, then I can help you but...
What do you know of spells? Are you familiar with trigger enhanced spells, because they are not hard and good to learn if you want some really cool spells 8)
I guess I can come up with some trigger enhanced spells off the top of my head though.
-One Dummy unit positioned over the Hero. The Dummy casts a ranged projectile when the Hero casts the fake ability. The projectile is sent to the targeted position that the fake abilities AoE is at. The fake ability could be Blizzard, Earthquake, or Silence( I like Silence for AoE abilities because there's nothing too much to change to make it do nothing offensive) Anyway, when the launched projectile hits the ground, another Dummy is created where the last projectile landed. The newly created Dummy launches the same projectile at a random point in a region around the current Dummy. Once the newly projectile hits, another Dummy is created there too. He does the same as the last two and you can repeat this about 8 times. You would stop the ongoing projectiles from the Dummy like this; after the last projectile has been lauched, simply don't create another Dummy. Altogether, when a Hero casts this spell, it looks like he throws a boulder (if the projectiles that are launched looked like boulders) and it hits the ground and bounces back up again. It bounces the same amount of times that the Dummy's shoot the boulders over and over. When it looks like the boulder "bounces", you could have the current Dummy that is under the "bounce" use Thunder Clap so that every time the boulder bounces, it damages all nearby units.
Well I didn't expect myself to create something like this in so little time but I have inspired myself

. If you do not come out with this then I might!