The Hiisi Poisoner (in-game name Myrkkyhiisi) is a tough Hiisi enemy. It shoots a poison projectile that has a Poison Trail behind it. This poison trail can deal damage to Hiisi on the ground below the projectile, so friendly fire is possible. However, the player should not rely on the Poisoner to kill its allies. It is quite a dangerous foe.
The Poisoner has a surprising amount of health. When fighting it, it is best to stay on the ground and fly above its projectiles. Stay on the ground to conserve your levitation force. Toxic Sludge Immunity makes this enemy a lot easier, as the poison is treated by the game as Toxic Sludge except it is purple. However, the poison projectile itself ignore Toxic Sludge immunity, in the same way a Fire Mage fireball ignores fire immunity. This enemy is one of the larger Hiisi, being the same size as the Hiisi Bomber.