x1 Fusion Essence
Fusion Core M1: Fuse with the nearest Arrancar next to you, granting a damage buff. While fused, you receive all 3 True Vastocar variants, regardless of what race the person you fused with is. The other person are also able to use their own moves once the white aura is gone, which is halfway through the duration of the fusion. At this point, control over the body is handed over to the person you fused with. Currently works with any race in party, and you share HP with the person you fuse with. If you fuse with a non-Arrancar, during their turn in the fusion you may lose 2 of the variants.

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Fusion Core M2: Sacrifice 30% of your hp, in return, you get a damage buff and a random True Vasto variants. However, this doesn't put you into combat, so you can just regen that 30% hp back in no time.