Card of the Week #31: Ghost of a Grudge
I sincerely hope that the use of this card is obvious to you, for the sake of the average quality of duelists at this academy.
In case you are a tree, I will explain how useful this effect can be. It can be used after your opponent declares an attack, which destroys their monster, nets you the equivelent of a direct attack, and also turns all of their other monsters into useless shells of their former selves. Any cards that were summoned that turn won't even be able to change battle positions, giving you free reign to deal tons through battle damage in your next turn.
Having 8 or more cards in your opponent's graveyard is not particularly situational, either. If it specified that the cards must be monsters, we may have more difficulty in using this card, but it does not; Spells and Traps count towards the 8 cards, meaning it's a very likely circumstance.
The card could potentially be used in a Chronomally deck as a stand-in for Fork. This could potentially make some form of Chronomally OTK viable in TCG format.
It's also a nice card for any cards that have effects that trigger when they deal battle damage. Cards like Don Zaloog will be able to surprise your opponent by making them drop a card along with losing whatever monster they attacked with if you can use this card in response to their attack.
Overall, this card is underrated and underused, and could be played in a variety of circumstances. It's very good for getting over high attack beaters, stopping your opponent from OTKing, OTKing your opponent, and protecting your monsters. That's a large number of uses for a card with only one effect.