well. a post a while ago got me thinking... it was the elemental one.
the elemental power source. i got thinking. hey! an Elemental defender!
evrythings fine (in my view) and im onto powers. lv3 Encounters to be precise.
now... is this too powerful for lv3 Encounter?
Trigger: One enemy makes a melee attack against an ally
Target:the triggering creature
Effect: the attack is cancelled and the target is knocked prone. If they stand up at any time until the end of your next turn, they take 3D4+ Wisdom modifier damage, and are restrained until the end of their next turn.
please tell me how i turn off this blasted return space thing? hwo am i meant to post when i cant even type blocks?
I'm not able to help with the balance, but you can single-space if you hold shift while hitting the enter key.
That looks
like this.
Good luck with the important part of the question. 
Yes it is too powerful for a level 3 Encounter.
Look at the Paladin L3 Encounter: Avenging Smite. Doesn't cancel the attack.
Or the Swordmage L3 Encounter: Dimensional Vortex, which is closer in power level, but does require a hit from the swordmage.
thank you.
I suppose this might be a good time to mention im creating a caster type class.
how about this.
Trigger:One enemy makes a melee attack against an ally
Target:the triggering creature
Effect: The attack is carried out as normal. After the attack has been followed through, the target is knocked prone. The first time the target stands up until the end of your next turn, takes damage equal to your Wisdom + Intelligence modifier.
thoughts?
I suppose this is a good example to say to Homebrewers that if a power or ability seems too powerful, then it probably is. But not necessarily the whole thing, just an aspect
General rule is that attack powers require attack rolls, and that level three powers are encounter attack powers.