Arcana Heart 3/Kayatsuhime
Kayatsuhime is the protective Arcana of the Inuwaka clan. It is said that Kayatsuhime and Moriomoto, the Koinu's (Konoha's) clan Arcana used to be of one entity. If Moriomoto can freely manipulate vegetation, then Kayatsuhime governs over the growth, prosperity and harvest; the fate over plants.
Roka - E moves charged to the max will drain some of your opponent's Arcana Gauge. This will not affect their maximum value though.
Petal Barrier - The Flower Arcana will automatically invalidate any counter hits on your character. It sounds plain but extremely effective in reducing massive and random damage from your opponent. Paired with the Flower Arcana's super fast Force Gauge recharge speed for bursts, this Arcana ends up being one of the most sturdy, defense-oriented Arcanas.
Extend Force Attributes
Invigorating Light - Activating EF will cause all of the plants on the stage to instantly mature one level. If a plant is already at level 5, then this will cause that plant to wither and die.
Single Blossom - E
This will send a flower-shaped projectile out in front of you. After it is out, it will pace forward in one direction. You can choose the direction it moves by holding the control stick up, down, left or right before it starts moving. This is almost a pure zoning tool as it is much too slow to be used in combos. However, the recovery is good, so if you land a hit on the ground you can step (66) then connect an A move for a combo. This move has a follow-up to it to expand its zoning capabilities...
Flower Storm - E [While a Single Blossom is out]
By inputting the motion again while a Single Blossom is out, you can cause the flower's petals to spread out to cover a larger area. The window for this is a bit restrictive; you cannot use it right after sending a Single Blossom out, it has to be on the move first. You also can't wait too long to do it. If it is already disappearing, you'll just end up doing the motion for Flower Storm but the flower will still fade away without scattering.
Illusionary Flower - E
Plants a flower in the ground. There are three kinds of flowers that will come out randomly. You can plant up the three at the same time and they will even last in between rounds. There are 5 stages to each flower. They will automatically mature due to the passage of time or rounds. As mentioned earlier, they will also mature if you use your Extend Force. When you are (very) near a flower, it will accelerate your Arcana Gauge recovery, or increase your max if you are already full. The more that are near you, the faster it will recover. At stage 5, after the normal requirements for a flower to mature, it will wither away.
Harvest - E
This move will allow you to harvest an Illusionary or Dream Flower from the ground. Each type of Illusionary Flower comes with different benefits at different stages. You cannot harvest a level one Illusionary Flower. The benefits are the same between each of the flowers up to stage 3. You can harvest a Dream Flower at stage one and the benefits are one of the Illusionary Flower's benefits at higher stages. The animation for this move will still come out even if you are nowhere near a flower, so be careful. Fortunately the whole duration of it is very short. As a matter of fact, you could use this move with some characters for zero gauge follow ups to 2Es (i.e. 2E → 623E → NH).
Multilayered Crimson Nivara - E
This is basically the super version of Single Blossom. It will automatically scatter out much like Flower Storm for an extremely wide attack area. There is no invincibility on this move, but it comes out relatively quickly for the kind of move that it is and is guaranteed to come out, so it has some functionality as a reversal. As said before, the area that it attacks is huge and it will keep your opponent blocking for a long time; it's quite easy to mix up your opponent off of this. Rather than a damage tool, this is a great set up tool.
Dream Flower - E
Plants a very large flower on the stage. You can only plant one of these at a time. The effects are much like the Illusionary Flower, but it grows much faster and the benefits are better.
Sakura Protector - Kayatsuhime attacks the entire screen with a sakura petal storm. The opponent can block this in the air. The petal blizzard in the beginning is a lock move, will damage the opponent after 19 more hits. It does hit the whole screen, so you could use this to punish the opponent if they are not paying attention to the fact that you are using this arcana since the start up is pretty fast. Unfortunately the damage is just "OK" so it's up to you if you want to risk not having Force Gauge for a while to use this.
Consult the Information Page to see the effects of Dream Flower and Illusionary Flower at each stage and the effects of harvesting them.