Niche D20When attempting to pin a target, a creature with the swallow whole ability may instead choose to swallow the target. If successful, the creature swallows its target; if the creature has a bite attack the swallowed creature takes damage equal to the bite’s damage dice. Unless otherwise noted, the target can be up to one size category smaller than the swallowing creature. The swallowed target takes damage each round, of an amount and type of damage determined by the individual creature’s statistics. When swallowed the target gains the pinned condition, while the creature that swallowed the target loses the grappled condition. The swallowing creature must still maintain the grapple may only do so once per round per creature swallowed as a reaction; success allowing the swallowing creature to maintain the grapple or pin condition on the target and dealing damage as noted of the swallow whole ability. The swallowing creature may not choose to do any other actions related to a grapple to a creature they have swallowed whole such as dealing damage not from the swallow whole, or tie up. If the swallowing creature fails to maintain the grapple once, the target loses the pinned condition and is instead grappled; the target remains within the creature still, but the swallowing creature cannot re-establish the pin while the creature remains inside them and may only further maintain the grapple.
When the target has escaped the pin, but is still grappled inside of the swallowing creature, the target may attempt to escape the grapple. If it succeeds the target escapes to an adjacent square of the creature that swallowed them. Additionally the target may attempt to cut its way out with a slashing weapon. The target must deal damage to the creature that swallowed it equaling to at least half its maximum hit points before it may cut its way out; the AC against these attacks is the creature’s flat-footed AC, but does not gain any Armor or Shield bonuses to its AC. This damage is tracked separately from the current HP of the creature, and does not allow a target to automatically escape once a creature is reduced to half hit points. Once a target has cut its way out it leaves a hole in the creature that swallowed it; immediately ending the grapple and allowing the target to move out of the creature’s square. This hole remains until the creature is brought back to maximum hit points or has restored hit points equaling half its maximum hit points.
Unless otherwise specified a creature may only have one creature one size smaller than themselves swallowed at one time, for each size category smaller than the swallowing creature multiply this value by 4; For example a large creature may have one medium or 4 small creatures, or 12 Tiny creatures. The creature must spend a separate reaction each round to maintain the grapple or pin for each creature swallowed.