Mizu no Ryū

Mizu no Ryū (Japanese: 水みず の 竜りゅう Romaji: mizu no ryū, and translated as Water Dragon) is, apparently, a water shamanistic summoning spell. These do not seem to be the Power Words of this spell.

The spell calls forth a water dragon. Its material is actually derived from the water itself, so it can be assumed that sufficient amount of water must be available nearby for the spell to function.

It seems that the dragon is controlled directly by the movements of the caster instead of verbal commands.

Naga the Serpent was capable of conjuring up a Water Dragon, but she was incapable of controlling it and turned against her. It was so powerful that it required Lina Inverse to take it down with a Dragon Slave.