This follower is seen absolutely everywhere in the endgame.
Starting from the T8 phoenix and then all the way through T11 and beyond with ashen phoenix, these followers are used in exceeding quantity. Every leaderboard and kingdom war screen is filled to the brim with the phoenixes.
In addition to being the most potent offensive utility follower -- 2x damage whereas others like Apollyon Apprentice and Chimera boast 1.5x -- it's also an extremely potent defensive follower -- 2x def/res(!), ward turn upkeep(!), and a protect chance(!). For a cherry on top, its skills are relatively high damage and high piercing (seen in Lusus3), and the burns/blights can help with second chance enemies.
Something has to give here. It was potent in the past, but with the addition of Blackened Eyes of Kerberos, its one weakness in having a lowish action rate was effectively removed. Now with +smartAI access, it doesn't need much action rate at all to turn into a Deific Channel machine.
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