Roll a 1d6 and:
if you roll 3 or lower you heal for ( rolled dice * your level) health
if you roll 4 or higher you take ( (rolled dice - 3) * your level) health
On Critical Success (1) : you add one more 1d6 to the rolls (up to 3)
if already 3 : heal by (1 * your level) then roll 3d6
On Critical Failure (6) : you remove one 1d6 from the rolls (minimum 1)
if already 1 : lose (1 * your level) health then roll 1d6
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