Luigi (SSBU)/Up special
Super Jump Punch is Luigi's most reliable KOing move, able to finish off opponents at around 50% to 60%. It has massive landing lag (45 frames), making it very punishable on whiff. Coming out on frame 8, it is one of Luigi's fastest out of shield options, but hindered by its low range. Aside from being Luigi’s primary recovery move for vertical distance, the move is typically used as a powerful combo finisher from a variety of Luigi's combo extenders, ending in a stock taken almost all the time. The move does not launch traditionally at 90°; instead, it has an angle of 88°. This means that optimal DI is away from Luigi.
In the air, it is noticeably weaker, but can be hit from an up tilt, a down throw and other combos and mix ups. It also has a slightly bigger hitbox that isn't extended into the z-axis, causing some inconsistencies against thinner characters. It is also able to start a combo should Luigi grab the ledge immediately after sweetspotting it. Unlike the grounded version, the aerial version sends straight up, using an angle of 90°.
When sourspotted, Super Jump Punch deals only 1% with knockback so weak that it cannot KO above the upper blast line, allowing two Luigis to perform the Luigi ladder technique. Combined with the high landing lag, this makes the late hit incredibly unsafe to land as it will inevitably lead to a very strong punish.
Landing a grounded clean hit triggers a Special Zoom.
The move enables ledge grabs from the front starting on frame 11, and from behind starting on frame 25. Luigi can also fast fall as early as frame 25.
To B-reverse the move, the control stick has to be held backward on frame 8 for the grounded version, and frame 6 for the aerial version.
While the move is generally described to only travel straight up, it can actually be directed horizontally much like Mario's version, albeit to a much less significant degree that is harder to discern.