Selected Alternate Racial Traits
Acid Breath: Gain a 5-foot cone breath weapon of acidic water usable once per day, dealing 1d8 acid damage per two character levels, maximum 5d8. A Reflex save halves the damage. This replaces the standard spell-like ability.
Amphibious: Gain the aquatic subtype and amphibious special quality, allowing the Undine to breathe both air and water. This replaces the standard spell-like ability.
Deepsight: Gain darkvision 120 feet while underwater but no darkvision outside water. This replaces darkvision.
Flesh Chameleon: Change natural coloration to a normal human skin tone, gaining +4 on Disguise checks to appear human. This replaces Energy Resistance.
Hydrated Vitality: Gain fast healing 2 for 1 round after fully submerging in natural water, healing up to 2 hit points per level per day. This replaces Water Affinity.
Nereid Fascination: Once per day create a short-lived 20-foot aura capable of fascinating humanoids. This replaces the standard spell-like ability.
Ooze Breath: Gain a 5-foot cone of slime usable once per day, dealing acid damage and potentially sickening creatures. This replaces the standard spell-like ability.
Terrain Chameleon: Change coloration to blend with underwater terrain, gaining +4 on Stealth checks underwater. This replaces Energy Resistance.
Triton Magic: Use summon nature's ally I once per day, but only to summon a dolphin. This replaces the standard spell-like ability.
Water Sense: Gain blindsense 30 feet against creatures in contact with the same body of water. This replaces Energy Resistance.
These options use the normal Pathfinder 1e alternate racial trait replacement rules.