User blog comment:KirbiMiroir/Make New Final Smashes Here!/@comment-25096445-20160406202015/@comment-25096445-20160410120007

It is not a clear reference to the Goddesses, as it's just an attack using the Triforce of courage. And of course it's one of the coolest moves a "living" cartoon character can use! It's one of the only ones! Now, I'm fine with Triforce Slash itself, but I would much rather they replace Triforce Slash as an attempt to de-clone Toon Link than keep it and have an un-inspired semi-clone.

Smash is a celebration of Nintendo's history. If you say it's ok to reference the Pokemon anime, then maybe in Smash 5 we'll get a stage based on the Mario Bros. cartoon or the Zelda cartoon.

Finally, yes the attack is Water-type, but that's because Greninja is a water-type. The attack is clearly based off a Night Slash, given that it's placed right in front of the moon. However, it might not be called Night Slash for two reasons: Night Slash is called Crossroad Killings in Japan, a reference to samurai testing their blades. Second, the move actually starts with Mat Block, and so that means Greninja is using two moves. I can accept that as the reason, however, Secret Ninja Attack is a stupid, stupid name.