Stardust gave me +2000 atk dmg with cebolla. Another problems was when i killed a monster with poison, and it made his health go below 0 ( e.g. -124) i had to wait untill he regenerated his health back to 0.
And i don't know if it is supposed to be like this, but when all my stats are +100 the other student still have like 10-30 stats.