Black Knight Irios
Explorer
Just for the record, there's no official ruling that's how that works, and the CharOp boards (who will stretch RAW to its limits mind you) rule that you damage yourself once before making any attacks on this turn and it applies to all of them. Since you use the power before you made a melee attack on your turn, it applies, according to them.
In my games, bloodclaw applies for the duration of an action/power (we've ruled that "attack" = "power" which is very ambiguous in the RAW but works for our group), so it can be very good with multi-attack powers, but it's not hideously broken when you go make 18 attacks in one turn using Follow-up blow, action points, free actions, and martial recovery (among other tricks).
I just want to point out that in the last WotC CharOp (reckless vs bloddclaw) thread the agreement was that the bloodclaw hit point cost has to be paid every timy you roll a d20 for an attack, e.g. Twin Strike costs 12HP if you want the bloodclaw effect on both attacks.
So I would be suffering 6 points of damage (from the bloodclaw gauntlets +6) and a -2 AC each turn to do +24 damage with my off-hand attack (the one with reckless on it) and a +30 with my primary attack (the one with radiant on it). This sounds amazingly broken, but do you think it is technically RAW?
You got it right except for the 6 damage which are 12 points of damage.