|Sell Creep Price:||21|
|Prevents goop effects.
The Siren's watery blasts can be a lifesaver when faced with toxic pools or patches of flame.
The Siren is a shotgun that fires a small spread of 3 water bullets. Upon hitting enemies or obstacles, its bullets leave behind pools of water. The Siren's pools of water can remove fire and poison puddles. While the gun is equipped, fall damage is prevented and the player is unaffected by goop on the ground and by the Phaser Spider's web.
- Brave New World - If the player also has Trident or Bionic Leg, while Siren is held, a fish companion follows the player that can block bullets and shows contents of chests without opening them.
- Bubble Trouble - If the player has Bubble Blaster, Siren will fire a single large shot that deals 18 damage, and Bubble Blaster's shots home in on enemies.
- Iron Stance - If the player has Heavy Boots, increases Siren's damage and knockback by 20%, increases shot speed by 50%, and decreases reload time by 20%.
- Siren Sidearm - If the player also has Barrel, the first shot of every Siren magazine fires two fish, and every Barrel shot fires a Siren water bullet.
- Removed: - If the player has Bionic Leg, Siren receives a 25% damage boost. Replaced with Brave New World.
- A Siren is a mythical creature that lures sailors to their doom, often portrayed as a mermaid.
- The Brave New World may be a reference to the DC Comic Superhero "Aquaman" who rules an underwater kingdom, wields a trident as a symbol of authority, and has a prosthetic hand.
- It is also a reference to the animated Disney film "The Little Mermaid", as the titular mermaid Ariel trades her voice for legs, her father Poseidon wields a trident, and the fish companion summoned by the synergy resembles Ariel's companion, Flounder. Additionally, Ariel sings a song titled "Part of Your World", alluded to in the synergy's name, "Brave New World". The gun is also colored the same as Ariel, with a green bottom (stock / tail) and purple top (foregrip / bikini).
- If the fish companion spawned by the Brave New World synergy shows the contents of a chest that only contains a pickup, it will show an AK-47 as the contents.