Piranha Plant (SSBU)/Up tilt
Piranha Plant shakes its head quickly upward. The move comes out fairly fast, and lingers long without a late hit, which, when combined with the head intangibility, makes the move a potent anti-air. It doesn't provide much hit advantage with the sweetspot at early percents, but can possibly lead into a grab if the opponent uses a slow option to attempt to hit Piranha Plant. At slightly higher percents, it can combo into itself, or forward tilt, and can combo into aerials at mid to high percents. At much higher percents, the sweetspot is able to kill, killing around the same percents as up throw, without DI. It is also able to reach the lower platforms of Battlefield, making it a decent sharking tool occasionally.
However, this move is not without its flaws, as it lacks horizontal range especially below, making it risky to use if the opponent isn't approaching vertically. Another issue with the move is that the sourspot on the stem has priority over the head hitbox, which can make the move kill inconsistently, although it provides better hit advantage at lower percents due to its increased base knockback. It is best suited as an anti-air mostly, as a result. By far the most prominent issue, however, comes from the attempted speed buff in 8.0.0, which erreneously altered the animation to provide a hurtbox extension and making the move have significantly more trouble hitting behind. This makes it a much more risky anti-air than it was prior to the attack speed buffs, as it is possible to extend the hurtbox and have it be beaten out by even moves like Snake's up aerial. Due to this, it is better to aim with the latter active frames, where the hurtbox extension is not present.