Planar Bestiary
An obsidian elemental is a variety of earth elemental summoned from the Plane of Earth. But because of their shape and demeanor, they're usually referred to as "obsidian stalkers."
The most common purpose given to a summoned obsidian stalker is to destroy a target or object. Alternatively, the obsidian stalker could also be tasked with recovering a specific object and returning it to the stalker's creator. Regardless of the task set them, the stalker accomplishes that task as poorly as possible, often twisting the command's meaning to the breaking point.
Once the task is complete (or the summoner dies), the magic that created the obsidian stalker ends and the elemental is released. When they are defeated or the magic that binds them expires or ends, an obsidian stalker falls into a pile of otherwise unremarkable obsidian shards.
As a creature of elemental stone, an obsidian stalker requires no air, food, drink, or sleep.
Motive: Fulfill commands of summoner, but indiscriminately
Environment: Anywhere in the multiverse
Health: 25
Damage Inflicted: Moderate wound (6 points)
Armor: 3
Movement: Long; short when burrowing
Modifications: Tracks and burrows as level 8; perception as level 9; stealth tasks relying on quietness as level 1 due to earthstorm aura
Combat: The obsidian stalker attacks twice each round with their claws or by flinging two obsidian shards up to long range.
The stalker can cloak themself in a swirling aura of obsidian shards as part of another action. The aura is noisy, reminiscent of windows shattering over and over. Any creature starting their turn next to the stalker or that moves next to the stalker takes 6 points of damage from the swirling shards, and on a failed Might defense task, is deafened until their next turn.
The stalker can momentarily extend the radius of their aura once every few rounds, intensifying it so much that all creatures within short range that fail a Speed defense task take 7 points of damage from flying shards, or 3 points of damage even if the defense task succeeds.
Obsidian stalkers are immune to poison attacks.
Interaction: Obsidian stalkers, if magically summoned to complete a task, are unreliable. They hate being called from their realm. If possible, they accomplish a task that technically fulfills the objective as worded, but that fails to fulfill the spirit of the command.
Use: An oddity seller offers a magic item they claim can summon an "obsidian elemental" that will do the bidding of the summoner. Depending on who gets the item, the resulting obsidian stalker could be used for revenge, thievery, or protection, or perhaps could be used by characters interested in helping others.
Loot: A defeated obsidian stalker leaves behind at least one expensive (250 gold coins) chunk of obsidian crystal. GM Intrusion: A character's ranged attack is defused and defeated by the obsidian stalker's aura of swirling obsidian shards.