Sorcery, R (1) You and target opponent each flip a coin. Mana Clash deals 1 damage to each player whose coin comes up tails. Repeat this process until both players' coins come up heads on the same flip.1
Illus. Mark Tedin
Each point of damage is dealt separately, so if you are damaged twice by this spell, each time is considered a separate time this source deals damage. This means you need power a Circle of Protection: Red twice if it damages you twice and you want to avoid all the damage. [8E FAQ 2003/07/28]
Always affects the caster and targets an opposing player. It cannot be Deflectioned back to affect the caster twice. [WotC Rules Team 1995/02/09]
This card's coin flip has no winner or loser. [8E FAQ 2003/07/28]