Fusing Personas in is the best way to create a powerful roster to aid you in battle, and Helel is a Persona worth fusing as early as possible. Unfortunately, Helel requires players to reach a fairly high level before they have the option to fuse it, so it will be available late in the game unless players grind up their level in Tartarus.
Helel is of the Star Arcana and has a base level of 88, with all its skills starting around 60. While a couple of combinations can produce Helel, players must first max out the Social Link associated with this persona, as Helel is the reward for reaching rank 10. It can be a lot of work, but unlocking the Armageddon Theurgy is worth it.
The first thing that should take priority on the road to unlocking Helel is ranking up the Star Social Link, Mamoru. He will not become available until August 2nd when you meet him at the Sports Meet, and even though this is when he unlocks, you will still not be able to engage with him until you have reached Rank 4 of the Courage Social Stat in . After unlocking him, he is available for hangouts on Tuesdays, Wednesdays, Fridays, and Sundays.
The main thing that makes Helel such a valuable Persona to fuse is the Armageddon Theurgy. Armageddon is one of the most powerful Theurgy attacks in, dealing 9,999 damage and making it capable of demolishing difficult enemies. It does come at a cost, reducing your SP and HP to 1, but it's still completely worth it if you have strong support. To unlock this Theurgy Attack, players will need to have both the Helel and Satan Personas.
When fusing near the full moon, an Accidental Fusion can occur. While this can be a good thing, as it can produce a persona of a higher level, it can also ruin your fusion by giving you a persona of a much lower level. There is no way to predict what will happen or when, but if it does, you will not receive the expected result from your fusion and have to do it all over again.
Several combinations that produce Helel require other
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