Prismatic Sphere

Prismatic sphere creates a shimmering, multicoloured globe of light that protects those within it from all forms of attack (it will normally appear as a hemisphere, with its lower half below ground). The sphere flashes with seven colours, each of which has a distinct power and purpose. It is immobile, but the caster can pass through and remain near it without harm. However, any other creature with fewer than 9 HD within 20 ft of the sphere will be blinded for 2d4 rounds by the colours if it looks at them. The sphere can be destroyed, colour by colour, in consecutive order, by various magical effects; however, the first colour must be brought down before the second can be affected, and so on. A rod of cancellation destroys a prismatic sphere, but an antimagic field fails to penetrate it. Dispel magic cannot dispel the sphere or anything beyond it (unless the first six colours have already been brought down). Magic resistance is effective against a prismatic sphere, but the check must be repeated for each colour present.

Each colour in the sphere has a different effect. The accompanying table shows the seven colours, the order in which they appear, their effects on creatures trying to attack the caster or pass through the sphere, and the magic needed to negate each colour.