Eidolon Form

An eidolon is the ghost of a living person, and the spell eidolon form turns you into pure spirit.

Cantrip

When you cast this on a creature, it starts turning back and forth from flesh to Spirit. Any time it is targeted by a physical attack, and it rolls assist to defend, the attack passes through harmlessly. The effect lasts as long as you concentrate.

Great

This transforms the target and all worn and held items wholly into Spirit. The target cannot interact with the material world, meaning they can't pick up items or be stopped by walls or be hurt by weapons and so on. Nor can they use social skills or spells to affect the physical, though they can be affected by such. In spirit form, the target can affect other spirit targets as if they were both physical beings interacting. Every time the target passes through a solid object, they lose 1 Spirit. The target moves by floating at their normal movement speed. The effect lasts as long as you concentrate. You can incorporate this spell into a weapon attack to bypass armor and intervening obstacles.

Superior

This turns the target into an eidolon as per the great version, but you no longer suffer Spirit loss when you pass through a solid object. Alternatively, you may turn a number of people equal to your Magic Power into eidolons, each following the rules of the great tier.

Ultimate

This turns a target into an eidolon as per the superior rules, but the target loses none of their ability to affect the physical world. They may still cast spells, make physical attacks that bypass armor, and use social skills.