Royal Rhino with Deceitful Dice - Phantom Nightmare (PHNI)

Once per turn, when a card or effect is activated, even during the Damage Step (Quick Effect): You can roll a six-sided die, then apply the appropriate effect, depending on the Chain Link number of this effect.
2: This card gains ATK equal to the result x 500 until the end of this turn.
3: Inflict damage to your opponent equal to the result x 500.
4+: Destroy cards on the field up to the result.