n large earth elemental 

Perception +16; darkvision, tremorsense (imprecise) 80 feet

Languages Terran

Skills Athletics +21, Stealth +12

Str +6 Dex -1 Con +7 Int -1 Wis +3 Cha -1

Earthbound When not touching solid ground, a stone mauler is slowed 1 and can't use reactions.

AC  27; Fort +23, Ref +15, Will +19

HP 180; Immunities bleed, poison, paralyzed, sleep

Spike Stones (aura, earth, primal, transmutation) 5 feet. Spikes of rock rise up from all stone surfaces in the emanation, creating difficult terrain. A creature moving in the terrain takes 2d6 piercing damage for each square of spikes it moves into (a Large or larger creature takes damage only once for each square it moves, even if its space covers multiple squares of spikes). Creatures with the earth trait ignore all effects within the area. The stone mauler can disable or activate spike stones as a single action, which has the concentrate trait.

Crumble [R] Trigger The stone mauler takes damage from a hostile source while atop rock or earth. Effect The stone mauler crumbles into the ground, Burrowing down 15 feet. This Burrowing does not trigger reactions. The stone mauler can't Crumble again for 1d4 rounds.

Speed 35 feet, burrow 35 feet; earth glide

Melee [>] fist +21 (reach 10 feet), Damage 2d10+10 bludgeoning plus Push 10 feet

Ranged [>] rock +21 (brutal, range increment 80 feet), Damage 2d12+6 bludgeoning

Earth Glide The stone mauler can Burrow through any earthen matter, including rock. When it does so, the stone mauler moves at its full burrow Speed, leaving no tunnels or signs of its passing.

Bestiary, page 147. Expanded in LOIL.