Peter presses on through the searing pain, his sword lashing out in hopes of creating an opening for his allies, his last stroke of defiance as his vision darkens.

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vanguard strike in hopes buffing the others

(1d20+7)[20] (includes aid another +2, +1 from furious counterstrike)
damage (1d8+4)[7] (includes+1 from furious counterstrike)

if hits, allies get +4 on attacks till start of next turn. Iron guard's glare ends when he goes unconscious. Wish I had taken the healing stance.

Then dropping into negatives.