REDU format ruling
Behemoth the King of All Animals

Nearest-era rulings (Tengu, Sept 2011) — no REDU-specific archive exists.
Card effect (current official text)This card can be Normal Summoned or Set with 1 Tribute. In that case, the original ATK of this card becomes 2000. When this card is Tribute Summoned, you can return from your Graveyard to the owner's hand a number of Beast-Type monsters equal to the number of Tributed monsters.
Rulings
- It is possible to properly Tribute Summon Behemoth the King of All Animals with just 1 Tribute. For example, you can Tribute Summon it with Trojan Horse, or use Cost Down and then Tribute 1 monster because Behemoth the King of All Animals is only Level 5. In cases such as this, either 2000 ATK or 2700 ATK is correct, so the controller can select which ATK it will have.
- If Trojan Horse is Tributed to Tribute Summon Behemoth the King of All Animals, you still only return 1 monster from the GY to your hand, because it’s the same number as the number of monsters you Tributed to perform the Summon.
- If Behemoth the King of All Animals is Tribute Summoned with 2000 ATK, and is then flipped face-down or removed from play temporarily, its ATK becomes 2700 points when it is again face-up on the field.
- If you Tribute Summon Behemoth the King of All Animals with 1 Tribute, and Skill Drain is activated, its ATK becomes 2700 points. Even if Skill Drain is destroyed, the ATK remains at 2700 points.
- If you Tribute Set Behemoth the King of All Animals with 1 Tribute, its ATK will only be 2000 points when flipped face-up. However, once it is face-up, if it is flipped face-down again, the effect is reset and its ATK becomes 2700 points.
- The second effect of Behemoth the King of All Animals is a Trigger Effect that can be chained to. It is a targeting effect that targets a monster(s) in the GY.
- If you Tribute Summon this card with 1 Tribute and equip it with Megamorph, its current ATK will become 4000 or 1000, depending on Life Points.
Rulings data courtesy of Format Library — formatlibrary.com. Spotted an inaccuracy? Flag it in the REDU forum — sourced change requests get reviewed.