The ③ effect:
You cannot negate the effects of a monster which already has its effects negated. The ④ effect:
Even if there is no "Red Dragon Archfiend" in your GY, this card will still return to the Extra Deck.
The effect that negates a monster's effect and increases the ATK of "Majestic Red Dragon" targets that monster.
The effect that activates after damage calculation activates even if "Majestic Red Dragon" would be destroyed during damage calculation.
The effect that activates during the End Phase targets 1 "Red Dragon Archfiend" in your GY.
The ATK gained by "Majestic Red Dragon" when you use its effect includes any bonuses the target monster is receiving from effects or Equip Spells.
If you target "Great Maju Garzett" with the effect of "Majestic Red Dragon", the ATK of "Great Maju Garzett" becomes 0 and "Majestic Red Dragon" will not gain ATK.
You cannot target a non-Effect monster with the effect of "Majestic Red Dragon".