| ok.. let's see.
Cleric, arguably weak, but i could see where it could come in handy if the DM throws lots of sneaky things around.
Fighter, Whoah... powerful... I'd basically never use anything else as a fighter. it's easily as or more powerful than some of the other low level powers.
Paladin, why is it usable with ranged attacks? otherwise decent it's slightly more powerful
Ranger, Pretty good compared to other ranger abilities, it has potential to the only attack used on anything with resistances.
Rogue, Not bad, i don't see it getting much use at higher levels due to the second attack being limited in damage potential but very nice for a brute rogue at low levels.
Warlock, good idea, I'd test it side by side with a version that attacked Fort and reflex(depending on the stat used) , but i don't see any warlock opting for a melee attack... ever. It may just be me.
Warlord, not bad as a basic power specially if the party doesn't have a fighter. But I'd make the mark come from an "Effect:" line so it works like the fighter mark, marking on a miss too.
Wizard, pretty good, it gives the wizard another reason to buy up Wisdom(or any stat for that matter) a good power for battlefield control. | 
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