Fiery Pufferfish and Trebuchet Combo Loop
This build only has a few necessary components but they're somewhat tricky to assemble.
Basically what you need is Fiery Pufferfish, Trebuchet, and a method to Haste ASAP.
Here's a quick TLDR of how the loop works:
TLDR Loop
- Haste at fight's start
- Fiery Pufferfish Burns when Hasted
- Trebuchet Hastes when Burns
Note: For whatever reason, Jellyfish overrides the combo so avoid having it on your board.
Oceanic Rush (your Haste method)

Vanessa has a lot of items and skills that relate to Haste, but Ocean Rush is among best-in-slot since it's an instant effect that procs with Aquatic.
Fiery Pufferfish
The hardest part of hitting this forbidden combo loop is Enchanting your Pufferfish into a Fiery Pufferfish.

To increase your chances, maximize your XP gain so you get the guaranteed Enchantment at level 16 (you still only get 3 choices so hopefully you roll the Burning Caldera).

At later days, you also have a chance to find it at the Burning items Vendor, Heff.
Trebuchet
Last but not least is the Trebuchet (you do not have to find the combo components in the listed order, feel free to pivot if you find them).
You can find Trebuchet at vendors that sell Large items or Weapons, or as a potential drop from the Infernal Frigate PvE encounter.

Note that Kripp granted a Poison Enchantment to his Trebuchet but it isn't necessary and was pretty overkill at that point