Most of that 'damage' is from Mare and Zebra.
Zebra does something like double your crit Damage. Mare buffs elemental weakness damage.
Tiara turns all of your damage to Water with her BB.
GSX gives you a huge crit buff, 75% at SBB10.
So all of your damage is Water, with 75% Chance to Critical Hit, which does along the lines of 50% more damage due to Mare's ability and then doubles on Critical Hits from Zebra.
Rumor is that Mare's ability might be bugged, as it (supposedly) only works on UNIT types in Japan. (Meaning you only get the bonus damage versus fire with water units, where in Global, it works with all elemental damage type, rather than unit type.)