[WRITTEN] Power Charge

[GGuardian]

Normal Spell Card

Target 1 face-up monster you control; The next Battle Damage your opponent would take involving that monster and a monster your opponent controls will be multiplied by 2.5 until this turn End Phase. You can only activate 1 "Power Charge" per turn.

[Fukato]

So this is a Persona related card? Because that's all I can think of... especially since in the game it actually boosts a character's next physical attack by x2.5 damage. It can definitely hurt the opponent if, I don't know maybe have a 3000 beater attacking directly for a significant amount of damage! That's 7500 battle damage to one's LP, so maybe have that effect only involve battles with monsters? Like Odd-Eyes? It can cause massive damage so yeah... it can be overpowering, especially if you target a monster like Beelze, who cannot be destroyed by battle or card effects. And this is a lingering effect, meaning once it is applied to that monster, it stays until the target leaves the field, or until the effect has been used. So maybe have it last for sometime only?

[Flash Flyer - Sakura]

As above mentioned, this card just screams OTKs.

Have it last until the End Phase of that turn only, AND make sure it's battle damage against a monster.

 

But yeah, Odd-Eyes can effectively use this to burn for 5x the amount of damage against most bosses.

(It already doubles the damage against them, so add this card's boost and yeah it'll hurt quite a bit)

 

Or better yet, just limit it to a smaller monster.

[♪ ♪Aria ♪ ♪]

A drawback is indeed essential for this card, also an added cost to make it more balanced like, the controller of the card  absorbs the same amount of damage dealt at the end phase of the turn and the monster is destroyed (e.g "Overcharged"), just an idea....