Bone Spurs (3.5e Spell)

With a painful squelch, bone spikes jut out of your skeleton, covering your body in hooks and razors.

When you cast bone spurs you deal 1d6 points of damage to yourself, and gain armor spikes all over your body. In addition you gain two natural slam attacks that deal 1d6 + Str bludgeoning and piercing damage (for medium creatures) with a 20/x2 critical. Any creatures grappling you also take this slam damage each round they grapple. Creatures striking you with unarmed attacks or natural weapons take 1d6 damage (no strength added). This however is not the real benefit.

You can extend the bone spurs deeper into your enemy at cost to yourself. You may deal 1 point of damage to yourself as part of an attack, gaining a +2 bonus to damage. Every 2 caster levels, you can increase the cost by 1 hp and benefit by +2, to a maximum of -10 hp/+20 damage at caster level 19.