Water Release

techniques are Water style Ninjutsu. Kisame Hoshigaki mainly uses these techniques and so did Zabuza Momochi before his death. The Seven Swordsmen of the Mist probably use these techniques or some of them (because only three have been revealed so far and one of them used Lightning based techniques, who was Raiga Kurosuki).

Water release techniques are probably the second common elemental techniques used by shinobi and mainly the Water Country.