For the purpose of Temple of Power's last ability, you need to have controlled the red source that dealt noncombat damage only at the time that the damage was dealt. If it dies or changes control after that point, that damage will still count toward Temple of Power's activation restriction.
Ojer Axonil, Deepest Might // Temple of Power
While you control Ojer Axonil, Deepest Might, if an effect such as that of Chandra's Pyrohelix asks you to divide damage among targets, you must divide the unmodified damage.
The comparison between the amount of noncombat damage being dealt and Ojer Axonil's power occurs only once, when the damage would be dealt. Reducing Ojer Axonil's power before noncombat damage is dealt may cause its replacement effect not to apply to that damage.
Magic: The Gathering · ™ & © Wizards of the Coast · Illus. Victor Adame Minguez
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