REDU format ruling
Max Warrior

Nearest-era rulings (Tengu, Sept 2011) — no REDU-specific archive exists.
Card effect (current official text)If this card attacks an opponent's monster, this card gains 400 ATK during the Damage Step only. If this card destroys an opponent's monster by battle, until your next Standby Phase: this card becomes Level 2 and its original ATK and DEF are halved.
Rulings
- The effect to change the Level and halve the ATK/DEF of this card is a Trigger Effect that activates at the end of the Damage Step.
- If "Max Warrior" has its Level and ATK/DEF changed by its own effect and your next Standby Phase is skipped, the Level and ATK/DEF of "Max Warrior" will return to normal at the start of Main Phase 1.
- If you use the effect of "Assault Armor" to let "Max Warrior" attack twice and destroy two monsters, its Level will be 2 and its original ATK/DEF will be ¼ of their printed value.
- You choose when during your Standby Phase to return "Max Warrior’s" Level and original ATK/DEF to normal. It does not start a chain.
- The halved ATK/DEF is considered the original ATK/DEF while "Max Warrior’s" effect is being applied.
Rulings data courtesy of Format Library — formatlibrary.com. Spotted an inaccuracy? Flag it in the REDU forum — sourced change requests get reviewed.