if you manage to get 13 orphans, one of the rarest yakuman in mahjong, you will do 32,000 damage to all enemies, more than any other attack in the game does to even a single enemy, yes including ultimate attacks ("mystic artes")
oh yeah and it also does 20% more damage in the evening. Nothing in the game tells you this, it just does.
-F
also that initial 1 damage per tile goes up for each time you use the spell, to a maximum of 100 damage per tile dealt
-F