Tremor Spike (Patreon)

Rod, rare

This industrial hollow rod is 3 feet long and weighs 15 pounds. The rod has a tapered spike on one end and an open, tower-like chimney on the other. Three hinged legs unfold from the sides of the rod, allowing it to stand upright with its spiked end pointed downward. Standing or collapsing the rod in this way requires an action.

The unfolded legs magically fasten the rod to the ground while its standing, but a creature can use its action to try to push it over with a successful DC 17 Strength check. Once the rod is no longer standing, it magically deactivates and collapses itself again.

As a bonus action, you can press a button on the standing rod to cause its mechanisms to churn and whir, repeatedly sending its spike into the ground below it. Pressing the button again deactivates the rod. The spike sends out loud, drum-like shockwaves every 6 seconds. The waves are audible out to 300 feet, or 1200 feet if a creature has tremorsense. If a creature has tremorsense, its range is halved while it's within 300 feet of the active rod. A creature can't perceive anything within 30 feet of the active rod using its tremorsense, but is aware that the disrupting shockwaves originate from that location.

The dwarf laughed as he watched his apprentice frantically cover his ears to block out the deafening noise of the spike, his shouted words mixing with the steady beat as he said, "If you think it's loud now, lad, just imagine how it'll be once we've riled the worms!"