REDU format ruling
Gorz the Emissary of Darkness

Nearest-era rulings (Tengu, Sept 2011) — no REDU-specific archive exists.
Card effect (current official text)When you take damage from a card in your opponent's possession: You can Special Summon this card from your hand. You must control no cards to activate and to resolve this effect. If Summoned this way, activate the appropriate effect, based on the type of damage:
● Battle damage: Special Summon 1 "Emissary of Darkness Token" (Fairy-Type/LIGHT/Level 7/ATK ?/DEF ?). Its ATK and DEF are each equal to the amount of battle damage you took.
● Effect damage: Inflict damage to your opponent equal to the amount of damage you took.
Rulings
- If "Caius the Shadow Monarch" banishes a DARK you control, while you control no other cards, you can Summon this card.
- You can't ever activate 2 trigger effects from your hand in the same chain, so you can't summon this card and "Tragoedia" in the same chain.
Rulings data courtesy of Format Library — formatlibrary.com. Spotted an inaccuracy? Flag it in the REDU forum — sourced change requests get reviewed.