Unique Mechanic #1: Grazing: Reimu has two hurtboxes. Her primary hurtbox, the size of a White Pikmin, is at the center of her entire model and any damage and knockback she takes from being hit there is doubled. (A fully charged Flare Blade would deal 100% damage instead of the usual 50%.) However, her secondary hurtbox, encompassing the rest of her body and surrounding her primary hurtbox, is different: all attacks that only hit the secondary hurtbox are treated as if they're parried, nullifying all damage and knockback that would have been dealt.
Unique Mechanic #2: Flying: Reimu's secondary jump is entirely replaced with the ability to fly. In this state, she can fly for twice as long as Peach/Daisy's Floating, but she can only access her aerials for that duration. Additionally, should Reimu move two Bowsers away from the point where she started flying, whether it be from moving with the joystick or using attacks that propel her in a direction, the flying will automatically deactivate. Reimu cannot access this flying until she lands on the ground.
Jab: A double slap and a kick. Based on her 5AAA from Scarlet Weather Rhapsody.
F-tilt: A forwards jab with her gohei. Has good range and has a sour spot on the paper frills at the end.
U-tilt: Reimu jumps upwards with both feet outstretched above her, giving this move some good range.
D-tilt: Reimu twirls her gohei in front of her. Similar to Palutena’s D-tilt, but hits multiple times.
Dash Attack: Jabs forwards with a single palm strike. While not dealing as much damage as one might think, it’s got good hitstun and is good as a combo starter.
Grab: Reimu holds the opponent in place with an amulet. For her pummel, she whacks them over the head with her gohei.
F-throw: Reimu launches the opponent with both her palms.
D-throw: Reimu jumps up and jabs her gohei on top of the opponent.
B-throw: Reimu flies behind the opponent and fires a barrage of needles that build up before she releases a large amulet that launches the opponent.
U-throw: Reimu channels power into the amulet, creating a rising pillar that launches the opponent upwards.
N-air: Reimu pokes her gohei forward, the end adorned with an amulet. This is a downwards-aimed N-air similar to the likes of Ryu, Ken and Terry.
F-air: Reimu flies forwards with a kick that deals some decent damage and can be used for evasion.
D-air: Reimu releases a powerful downwards palm that deals a meteor strike at the center of the move, and has a windbox surrounding it.
B-air: Reimu whirls her gohei behind her. This has good range, meaning it’s safe to attack with, but it doesn’t deal as much damage and isn’t a good kill tool.
U-air: A fiery crescent kick over her. Based on her Ascension Kick from the fighting games.
Side Smash: Reimu reels back and lunges forwards with both her palms, covering some good distance along the ground.
Up Smash: Reimu raises a palm above her for a moment, then creates a pillar of rising amulets that hits multiple times. Like Palutena’s Up Smash, this has some of the highest vertical range in the game, but unlike Palutena, this hits multiple times on both sides of her.
Down Smash: Reimu summons an amulet to travel along the ground in front of her, dealing damage to anyone in its wake. This can be changed to attack behind her instead of in front.
Neutral B: Hakurei Amulet: Reimu summons one large amulet and four smaller amulets and fires them in a spread. By tilting the joystick after pressing B, you can change the trajectory of the attack, and this can be used in mid-air.
Side B: Yin-Yang Orb: Reimu fires a large Yin-Yang that can be aimed. This projectile shares the same properties as Meloetta’s Relic Song, except the projectile disappears the moment it hits an opponent.
Up B: Floating Wall Jump: Reimu creates a barrier beneath her feet and jumps upwards. This has only fairly decent vertical distance, but like Cloud’s Climhazzard, an extra button press can send her downwards. The first attack can also aim downwards before returning upwards for mind games.
Down B: Dimensional Rift: A move that differs based on how long you press the button. Reimu will disappear from reality, then reappear to perform a certain attack. Lightly tapping B will perform a hurtling head stomp some distance in front of her. Holding the B button will perform a sliding kick that hits three times. The former can’t meteor spike but is good at gimping, and the latter is a good combo starter.
Final Smash: Fantasy Seal: Reimu releases a giant barrage of large multicolored orbs that hone in on all enemies on screen. They deal massive damage and absorb all other projectiles that they touch.
In short, Reimu is a highly-evasive glass cannon who possesses one of the best recovery games in the entire roster. Her survivability, contributed to by her flying, her parry-based secondary hurtbox and fast movement speed, is unparalleled and makes her projectile game all the more terrifying to come up against. However, she is extremely frail and terrible at close-quarters, with a less-than decent grab game, a distinct lack of keepaway and a primary hurtbox that doubles the damage she takes from enemies. Anyone who isn't too careful when playing as Reimu would experience some of the quickest stocks at their expense.