The Acidgrinder is a fishing rod shaped like a chainsaw, complete with green and purple glowing effects that resemble paint splatters. You get it by completing a series of quests from Axel at the Underground Music Venue. It's not the easiest rod to unlock, but its unique charging mechanic makes it worth the effort once you have it.

What is the Acidgrinder?

The Acidgrinder is a mid-tier fishing rod with a standout feature: a hold-to-charge mechanic. Unlike most rods, you can hold down an input to build up charge, which increases your progress speed and forced progress speed by up to 50%. Letting go reduces the charge, so timing is key. This makes it feel similar to the Maelstrom rod but with its own twist.

How to Unlock the Acidgrinder

You unlock the Acidgrinder by completing all three of Axel's quests at the Underground Music Venue. Here's what you need to do:

  1. Catch a Tainted Brine Phantom — This is your first quest. Find and reel in a Brine Phantom fish with the Tainted mutation at the Underground Music Venue.
  2. Catch a Brined Brine Sovereign — Next, catch a Brine Sovereign with the Brined mutation. Completing this quest rewards a restricted version of the Acidgrinder (you can use it, but it has limitations).
  3. Catch and return an Acidic Caustic Starwyrm with Acidgrinder — Use the restricted Acidgrinder you just earned to catch a Caustic Starwyrm with the Acidic mutation, then return it to Axel. Completing all three quests gives you the unrestricted version.
💡 Tip — The third quest requires you to already have the Acidgrinder, so you're locked into using it for that catch. Make sure you're comfortable with the charging mechanic before attempting the Caustic Starwyrm hunt.

Rod Stats & Passives

Here are the Acidgrinder's key stats:

  • Lure Speed: 83% — Below average for attracting fish.
  • Luck: 185% — A major strength; much better than average for rare mutations.
  • Control: -0.02 — Slightly harder to follow the blue line during reeling.
  • Resilience: 30% — Below average; you'll break the line more often on mistakes.
  • Max Weight: Infinite — You can reel in any fish, no matter how heavy.
  • Durability: 200 — Works in Lava, Noxious Fluid, and Brine environments before needing repair.

The Acidgrinder's passive abilities are where it shines:

  • Acidic Mutation Chance: 40% chance to trigger the Acidic mutation on fish you catch (a 7.3x rarity boost).
  • Charge Mechanic: Hold an input to build charge, which boosts your progress speed and forced progress speed by up to 50%. Release to decrease charge. This is your main tool for landing tough fish.

Tips for Acidgrinder Success

💡 Tip — The Acidgrinder's high luck stat means you're very likely to get Acidic mutations on your catches. If you're hunting mutation variants, this rod is your best friend.

Master the charge timing. The hold-to-charge mechanic takes practice. Build charge during calm moments in the bar-following minigame, then release it strategically to push through tough spots. Don't waste it all at once.

Use it in the right biomes. The Acidgrinder has 200 durability in Lava, Noxious Fluid, and Brine environments. If you're fishing elsewhere, durability lasts longer. Plan your trips accordingly.

Pair it with patience. The 83% lure speed is slow, so expect longer waits between bites. Use the shake mechanic (mentioned in the game's core fishing tutorial) to speed up fish attraction if you're getting impatient.