One of the most prominent strategies of the Water Attribute is the Water Xyz strategy
Four mana is a massive cost, a creature has to be Titan levels of good or you have to have vast amounts of spare mana before you are paying it
It also has an effect that can play a Tamer when this card suspends, so you can use this card in the opening turns to play [BT16-085 Davis Motomiya & Ken Ichijoji]
Im not even a huge franchise fan (Ive played almost all of 7, and all of 7: Remake, 7: Rebirth, and 16) but I was hooked on the draft format
By playing your own walkers you can take advantage of the downside and destroy the world heavily in your favour board position wise
Martial Metal Marcher is a level 3 Synchro monster that also happens to be a tuner, which makes it significantly easier for players to climb through multiple Synchro monsters throughout the turn