Edison format ruling
Spell of Pain

Card effect (current official text)When your opponent activates a card or effect that would inflict effect damage to you: Your opponent takes the effect damage from that card or effect, instead.
Rulings
- "Spell of Pain" ‘switches’ damage, like "Barrel Behind the Door." It does not actually have an effect itself that ‘inflicts’ damage. "Spell of Pain" is chained to an effect that would inflict damage to you.
- You cannot activate "Spell of Pain" during the Damage Step.
Rulings data courtesy of Format Library — formatlibrary.com. Spotted an inaccuracy? Flag it in the Edison forum — sourced change requests get reviewed.