![Riftbound Spell: Imperial Decree. [Action] (Play on your turn or in showdowns.)
When any unit takes damage this turn, kill it.](https://cmsassets.rgpub.io/sanity/images/dsfx7636/game_data_live/fc6ab617f1ce20c82ed76dc6446d42d416c08b34-744x1039.png?accountingTag=RB&w=744&fm=webp)
What happens when I play Hextech Ray on an Elder Dragon while Imperial Decree's delayed trigger is active and I have an Immortal Phoenix in the Trash? Can I play Immortal Phoenix from the Trash?
You can.
Per the current rules, there is nothing that would stop Imperial Decree's delayed trigger from triggering Immortal Phoenix. It is a triggered ability generated by a spell; it is attributed a kill action, and thus the spell that generated it will also be attributed the same kill action. The owner of Imperial Decree is the controller of the delayed triggered ability; the player responsible for the kill action is the one who controls the ability; and that same player is the owner of Immortal Phoenix in the Trash. Thus all three conditions for Immortal Phoenix triggering are complete, and it will trigger.