Old game, rpg ? gauntlet ? Hack'n'slash ?

Hello !

So i'm looking for that old game i played 20 years ago. It was a fast paced game. From what i remember, it could have been a mix of rpg, gauntlet and hack n slash.

You could chose between a few classes. I remember at least a mage and a warrior.

The scenario was something about Rats ? I don't know if the ennemies were rats or if you played rats.
It was somewhat pixelated, and the view was from top. I think the game was already a bit old but was after 3d. I remember some cinematics in low polygon 3d. One was with a crystal floating in a room. I think it was red. and talking to the player about cleansing a castle ?

Thanks for the help <3

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