Official Rulings
My opponent has Chronophage (DT 017) in play, with 2 damage on it. I play a creature that has a damage bonus icon on it, and apply the damage to my opponent’s Chronophage. Did my creature still gain the Omega keyword, meaning I end the step, or was Chronophage moved out of play before its ability could resolve on my creature, meaning I can continue to play and/or use cards in the current step?
The creature that was played gained the Omega keyword as it entered play, so the Omega keyword will resolve as if it were on the card when the card was played.
Source: Rulebook
My opponent has Chronophage (DT 017) in play, with 2 damage on it. I play a creature that has a damage bonus icon on it, and apply the damage to my opponent’s Chronophage. Did my creature still gain the Omega keyword, meaning I end the step, or was Chronophage moved out of play before its ability could resolve on my creature, meaning I can continue to play and/or use cards in the current step?
The creature that was played gained the Omega keyword as it entered play, so the Omega keyword will resolve as if it were on the card when the card was played.
Source: Rulebook
Commentary
The Omega keyword granted by Chronophage's ability will resolve (resulting in the end of the current step), even if another Play: or "After Play" effect destroys the card upon entering play.
Source: Duskwitch
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