empower of the oni

This spell helps the users giving them the power of the oni they can cast a hellish fire and making them look like one with temporary armor that of a samurai and an oni mask that grants armor level 20. this person has life steal for one minute and can summon fire and a fire blade, but the more power it uses the less time it has in that form the users has one minute and a total of 4 rounds but every time the users uses one of the power it drains the power of the person and shortens the time in that form the users can also heal teammates but it takes a huge chunk of time out of the users.the final thing is the users has to immediately use this spell its called the oni domain it makes a impenetrable bubble and burns the enemy but only one person can go in. the down side is once the person gets out of that form they have to take a long rest.