I have just beaten Zephys in Heorot castle, he said “I will give you some of my power” (or something like that), but I cannot find it in my Arkadion list. Where is he?

These spirits join you in battle through summoning. The summoning gauge can be seen below your hero in battles. When it’s full, you can summon your spirits like zephys into battle.

He is a firstone, which is a special type of arkadion. As you defeat enemies and take damage a bar under your Heroes picture slowly fills. When this is full you can tap your hero and summon any of the first ones you have currently obtained to help you win that battle.

This bar will reset to 0 when a firstone is summoned or if you go back to town to rest

Thank you very much for the answer