Step on a trigger, often a floor tile, and get hit by a poison dart. This one is covered in bloodroot poison.
Detect: Per-based Traps at -2.
Disarm: DX-based Traps at -1.
Circumvent: Automatic (don't step on the trigger).
Effects: 1d-2 small piercing plus poison; one minute afterwards, resist vs. HT at +1 or lose 1d-3 each HT and Will.
Rearm: Yes, if you have more darts and poison.
If you cover the dart in small monstrous centipede poison, it does 1d-2 small piercing plus poison; resist vs. HT at +2 or lose 1 DX; do the same one minute afterwards. Sprugtooth recommends putting many darts in this trap; it can target everyone in a 2-hex radius if you wish.