These four-pronged metal spikes can cause damage to a creature’s feet. You can scatter caltrops in an empty square adjacent to you with an Interact action. The first creature that moves into that square must succeed at a DC 14 Acrobatics check or take 1d4 piercing damage and 1 Persistent Damage. A creature taking the persistent damage from caltrops is Hampered 5. Spending an Interact action to pluck the caltrops free removes the Persistent Damage condition. Once a creature takes damage from caltrops, enough caltrops are ruined that other creatures moving into the square are safe.
Deployed caltrops can be salvaged to be used again if no creatures took damage from them. Otherwise, enough caltrops are ruined that they cannot be salvaged.