Hazardous Waste Dump

Someone (me ) doesn't want you in this area, or what are those Big Ugliez doing here?

A long-range weapon would be nice … like a Boomerang , maybe?
That would also mean another five Goo Puddlez , if you "put them down for the count".
But one of those Gruntz is standing on a Goo Puddle , so you don't want to finish him off where he is standing, and lose some Goo! Can you get him to move from there, and conserve his Goo?
"Whoa! Where did that guy come from?" (Consider it a bonus ... another Goo Puddle 'on the hoof'.)

Oh! CheckPoint Switchez (CPS)! A Checkpoint that requirez a Warpstone Grunt and any other Grunt to pass it. That must be it.

Last Obstaclez to pass, right? Wrong!
Remember that a Warpstone Grunt doesn't fight very well … in fact, doesn't fight at all!
If you look ahead, you will notice that three Gruntz are necessary in order to enter the King's Fortress.
And there is another Grunt nearby who may turn out to be a bother.

Red Pyramidz (RP) in your way? Maybe you did thingz in the wrong order, or at the wrong time?
Do you have a way available to trigger a Red Toggle Switch (RTS) somewhere?
Like a Rolling Rock (RR)? Or a Grunt who can reach a Red Switch of any kind ... RTS or Red Hold Switch (RHS)?
If you haven't released the RR , is the Crumbling Bridge (CB) still in place to allow the RR to reach the Red/Green/Red Toggle Switchez area?
Or maybe, if you just wait a while, the RPz will go down because the RR hits a Red Switch for you.
At any rate, you know at least two Grunz have to pass through this area (and survive!).

What's that twinkling in there among the cratez? Somebody really should go investigate that!
Maybe it is also possible to pick up that Coin near the Border area?