The Triforce of Wisdom is Zelda's Final Smash in Super Smash Bros. Ultimate, replacing her original Final Smash, Light Arrow.
Overview
Similarly to Link's previous Final Smash Triforce Slash, Zelda catches opponents directly in front of her and seals them away in the Triforce of Wisdom. Zelda sucks in any immediate opponents, trapping the closest one and dealing significant damage. Once the Triforce disappears, the sealed opponents will be returned to the stage, suffering severe knockback. If the target is at 100% damage, they will be instantly K.O.’d.
Origin
The Triforce of Wisdom is one of the three pieces of the Triforce, a sacred relic that has appeared throughout the Legend of Zelda series. Zelda is commonly its keeper or guardian in most games.
The usage of the Triforce of Wisdom is likely based on the final battle against Ganon in Ocarina of Time, where Zelda uses its magic to trap Ganon long enough for Link to deal the final blow.