When you have entered the Hibernation Chamber through the windmill door, the blaster is in the arms locker at the upper right of the chamber. Get it and take the elevator down to fight the boss plant monsters.
I think its up the monsters butt, love ameister
You use it to beat the plant boss at the end :)
For most of the monsters, you can use the weed-whacking attachment on your mech. If that doesn't work, shoot them with the toxic blaster attachment.
First you get up on the machine then equip on the Toxic Blaster then when the monster attacks you try to miss its attacks, but when it opens its mouth use the space bar and hit as many times as you can! Save
its in the museum on mainstreet of steamworks island :)
It's Steamworks Island #14th Island
(The solution is at the related question "How do you beat Steamworks Island")
the crab on steamworks island is next to the living quarters
You go to Steamworks and head to the museum and there is the Deogen
steamworks island
There is a video walkthrough at the related link below. There are written WikiAnswers solutions at the related questions, as there are for all Poptropica islands. (How do you beat Steamworks Island) (What is the walkthrough for Steamworks Island)
Steamworks island