"This sh.it has started to piss me off now." Zaen mumbled as the kill zone dissipated around him, "Can anyone here die after being killed once?"
The artefact might have told him that Aldo was dead but even Zaen had enough brain cells to know that it wasn't the case. Dying people do not give threats and judging by the ability Aldo had, it was completely possible that the Aldo Zaen had killed was simply another clone and not the actual person.
Zaen was surprised when he had to fight Chris again, but even then he wasn't half as pissed as he was after fighting Aldo. He also foolishly used the silent kill zone there thinking that his secret spell would remain a secret after he killed Aldo. However, that won't be happening anymore because Aldo wasn't dead, dead.