Yukiko has an alternative way of KOing. In order to to achieve this alternative KO move, Yukiko must first knock the opponent down to the ground. After she does that, provided that the opponent is on the same ground level and is within 2 stage builder blocks, press any taunt to quickly have the following thing to happen below:
Just for those who don't know, that guy is suppose to be Jeff Hardy, my MYM 7 set.(wary)
Yeah, it's time for an all attack! Press A to confirm yes, and Yukiko will then rush in, attacking the opponent with a barrage of hits, with smoke and cartoon signs. At the end of the 3 second animation (which cannot be interfered), the opponent suffers 15% damage with knockback KOing at 80%. Ouch. Press B to say no, and Yukiko will cancel it. When Yukiko wants to perform an all out attack, the opponent can't get up.
Example of an All Out Attack. The pains i had to go through to get this GIF...
Of course, the opponent has a chance to fight back. If you're at a percentage that's higher above 20%, the opponent can button mash A 5 times within 3 seconds. If they are within 20% damage, it'll take the opponent 10 button mashes, while if your percentage is lower by more than 20%, it'll take 15 button mashes. Of course, there are ways to guaranteed those seconds, but I'll explain that later. If they do manage to avoid an all out attack this way, Yukiko will be knocked down herself, right next to the opponent.
Now, in a match with at least 3 characters, if one of the characters (besides Yukiko) is knocked down, the other opponent (whether it be teammate or foe) can perform a taunt to initiate an all out attack of their own. This time though, they'll temporally team up with Yukiko, and for every extra character in the assault, it'll deal off an extra 15% damage, for a max of 45% damage, with 3 allies. In this event, it's impossible for the opponent to fight back. However, other allies/Yukiko can choose to say no to the assault, thus auto ending it, though it at least works if Yukiko and one other ally helps you.
An image similar to this quickly appears when choosing to say Yes to the all out attack. In a 1 vs 1 match, only 2 boxes (Yukiko and the opponent) will appear. Every time though, the bottom image is the opponent's that's going to be beat up.
The interesting part is that each character from Brawl says something different when they want to start an all out attack. These include:
Neutral Special - Persona Summon
Konohana Sakuya
A card appears in front of Yukiko, and she'll take a quick swing at it with her fan, destroying it, which only takes a second. Suddenly, it'll summon her Persona, as seen above. With this Persona, she'll have access to new attacks, which may help her depending on the situation. Just remember that when summoned, it'll appear in front of Yukiko when doing so. Her Persona will always be following her around, no matter where she goes. However, if you simply decide to tap B, her Persona will stay still where you pressed it, and you'll regain your usual moveset. Holding B for a whole second will cause it to disappear again.
Example of Yukiko summoning her Persona using her forward smash.
Now, sure it replaces some of Yukiko's moves, but what else can it do? What if i told you that if her Persona's summoned out, it counts as an extra character for her All Out Attack, so you could do 30% damage to the opponent? Not only that, when attacked, her Persona never suffers any knockback. The disadvantages to having her Persona out, as when attacked, all the damage is instantly redirected towards Yukiko (though only 3/4ths of the damage will be dealt). Considering how big her Persona is (a bit bigger than Ganondorf)...you best not have her Persona out for too long.
Fire Attacks that her Persona does can also set the opponent "on fire", suffering 1-2% damage a second, and after 5 seconds has passed, they'll automatically collapse to the ground from exhaustion. They'll be guaranteed to stay down for 2 seconds this way, giving it a perfect opportunity for an All Out Attack. Note that in the air, the countdown will pause. However, if they decide to roll around 2 times in a row, the status effect will disappear. Stop, drop and roll, remember?
Side Special - Fan Blow
Yes, the move is as generic as it sounds. There are actually 2 uses with this move though. Simply tapping B will have Yukiko swing her fan vertically downwards, blowing opponents within a stage builder block of range away by 1.5 stage builder blocks, making it a decent spacing move. This has very little beginning lag, but average ending lag and that's about it. Can also be used to move things forward, or get rid of stuff.
Holding B will have Yukiko blow the fan on herself to cool herself like an elegant priestess (that's what fans are used for, right?). Anyway, doing this will heal Yukiko 2-3% damage per second she's holding the B button. Has very little startup, but average cool off when you decide to end it. Not an attacking move in anyway, but is good for buffing off any hits when Yukiko's Persona's out.
Up Special - Backside Of The TV
Yukiko snaps her fingers, and suddenly a TV appears above her head (yeah, it's a prop, what are you going to do?), causing her to jump in, which takes half a second. Now, the TV quickly turns into a cursor, that can't be hittable, and you can move it for 2 seconds, being able to go up to 5 stage builder blocks in a straight direction, though you can end it later by pressing B. Yukiko will then reappear from the TV, which takes half a second. This is useful for repositioning Yukiko, which can also be very useful for separation of her Persona.
On the ground, the TV appears in front of Yukiko (which lasts for 5 seconds), and she can choose to move into it if she wants, and it reappears facing in the direction Yukiko is facing. However, note that any object, and only 1 object can go through it, so be careful when using this move. If an opponent or their projectiles go in the TV, they themselves can move the cursor.
Down Special - I'll Face Myself
Yukiko will touch her heart area, and with a second of waiting, suddenly a cage will surround her, representing Yukiko feeling trapped within herself and it's as big as her. While in this cage, which has 40% damage to break, Yukiko can't suffer any knockback. Yukiko also can't move while in the cage, though she can attack it herself, and any projectiles she does will go through the cage, while still doing damage to it. Note that if the opponent attacks the cage, they'll also do damage to Yukiko.
So what's the point of this cage you ask? Well, if Yukiko breaks the cage, she'll overcome her inner self (or something like that), and her Persona will transform into "
Amaterasu," which grants her Persona (and ONLY her Persona) moves half the amount of lag, and boosts moves like healing and damage boosts by 5%. In the event that the opponent breaks the cage, Yukiko will be grounded on the spot.
Using this move after her Persona's transformed will have Yukiko still touch her heart area, but this time, if the opponent's within a 2 stage builder block range, they'll be trapped in a cage this time, forcing them to go through the ordeal Yukiko went through, though it's only 30% strong. If Yukiko breaks their cage, they'll then be knocked down to the ground. This would be great for an all out attack, as mashing A is pointless for 1 second if knocked down this way. If the opponent breaks the cage, they'll force Yukiko's Persona to return to it's original form.