Activate Spawning Pit's second ability by paying ({1} magic symbol) and removing two charge counters from it, creating two 2/2 Spawn artifact creature tokens.
Activate Spawning Pit's first ability twice by sacrificing both Spawns.
The Spawns die, triggering Pitiless Plunderer twice, creating two Treasure tokens.
Resolve both Spawning Pit abilities, putting two charge counters on it.
Activate a Treasure by tapping and sacrificing it, adding ({1} magic symbol) .