Bony spurs or chitinous spikes protrude from your joints, giving you a jagged profile and making you dangerous to grapple.
Benefit
Your jagged spurs deal 1d4 points of piercing damage (assuming you are Medium size) and can be used exactly as if they were spiked armor. Furthermore, you deal 1d4 points of piercing damage per round to any creature that swallows you using the swallow whole ability.
Special
If you wear armor of any kind, however, it covers your spikes and prevents you from using them. Special armor can be crafted to accommodate your spikes; however, this typically does not increase the price of the armor,