REDU format ruling
Cocoon Veil

Nearest-era rulings (Tengu, Sept 2011) — no REDU-specific archive exists.
Card effect (current official text)Activate by Tributing 1 face-up "Chrysalis" monster. This turn, any damage to a player caused by an effect becomes 0. Special Summon 1 "Neo-Spacian" monster written on the "Chrysalis" monster you Tributed from your hand, Deck or from either player's Graveyard.
Rulings
- You cannot activate this card if you cannot Special Summon a monster due to the effect of Scapegoat, etc.
- Tributing a Chrysalis monster is part of this card's effect, not a cost.
- There is no specific activation timing for this card. Any effect damage done to a player after this card resolves is reduced to 0.
- The damage reduction and Special Summon effects of this card are indepentant of each other. You Special Summon as part of this card's resolution, not the first time damage is reduced to 0 by its effect.
- You cannot activate this card if a Neo-Spacian monster written in the text of a Chrysalis monster you can Tribute for its effect is not in your hand, Deck or either GY.
Rulings data courtesy of Format Library — formatlibrary.com. Spotted an inaccuracy? Flag it in the REDU forum — sourced change requests get reviewed.