Akroma, Angel of Fury can’t have it’s mana drained or raised according to it’s card.
But trying out decks with Reliquary Tower it still drained Akroma every turn.
And when playing in TG, the opponent deck cast Mizzium Meddler that also drained mana from Akroma.
I then checked Carnage Tyrant to see if it was the same but it couldn’t be drained so worked as intended.
//Edited Title - Brigby