REDU format ruling
Outstanding Dog Marron

Nearest-era rulings (Tengu, Sept 2011) — no REDU-specific archive exists.
Card effect (current official text)When this card is sent to your Graveyard, add it to your Deck and shuffle it.
Rulings
- When Outstanding Dog Marron is sent to the GY during a chain, its effect is activated after the current chain resolves (just like Witch of the Black Forest).
- When Mystical Knight of Jackal attacks Outstanding Dog Marron and destroys it, the effects are simultaneous. So Mystical Knight of Jackal's effect is Step 1 of a chain and Outstanding Dog Marron is Step 2. Outstanding Dog Marron is returned to the Deck and Mystical Knight of Jackal's effect disappears.
Rulings data courtesy of Format Library — formatlibrary.com. Spotted an inaccuracy? Flag it in the REDU forum — sourced change requests get reviewed.