A cloud of invisible magical sensors in a 10-foot radius surrounds an invisible wall or floor rune the size of the creature to be summoned.
Complex
Magical
Trap
Level
1
Complexity
Complex
Kind
Magical trap
Traits
Complex, Magical, Trap
Stealth
+7 (trained)
Disable
DC 15 Acrobatics to approach without triggering the trap followed by DC 17 Thievery (trained) to erase the rune, or dispel magic (1st rank; counteract DC 15) to counteract the rune
Reset
The trap resets each day at dawn.
Summon Monster (Reaction)
Arcane
Trigger A creature enters the cloud of magical sensors; Effect This trap summons a specific 1st-level creature, determined when the trap is created. The creature rolls initiative and remains for 2d6 rounds, after which the spell ends and the creature disappears. The creature also disappears if someone disables the trap before the duration expires. The summoned creature can use 3 actions each round and can use reactions, unlike most summoned creatures.
Reset
The trap resets each day at dawn.
Source: Pathfinder GM Core, p. 108
Bring Summoning Rune into a Pathfinder 2e game with The DM Screen.