The goblins get past the wizard Niak's mad dog, Ragnarok, and sneak into the wizard's house.
How to Clear Gobliiins Level 12
Switch to 
Dwayne/Oups and change the cursor to an open hand.
Click the cup and ball (beneath the window) to pick it up. Then
change the cursor into a fist and click the skeleton's hand on the desk
to give the toy to
the skeleton.
Then change the cursor to an open hand and click the feather in the inkwell on the desk. Then change the cursor to a fist and click the skeleton's foot. A key will pop out of its skull. Make sure you have given the cup and ball to the skeleton (see previous paragraph), then change the cursor to an open hand and click on the key.
Then change the cursor to a fist and click on the cage that the hand is coming out of. You will give the key to the creature inside. It will open the cage and go out the window.
Switch to 
Hooter/Ignatius and change the cursor to a fist, and click
the feather. It will turn into a flyswatter. Have Dwayne/Oups
pick it up and stand on the upper shelf, and use the
flyswatter to swat the bee when it lands on the upper shelf. If it
flies away, just wait for it to stop on the top shelf again, then swat it.
Then have Hooter/Ignatius use magic on the bee to turn it into a
dart. Then have Dwayne/Oups pick up the dart, change the cursor
to a fist, and click the portrait of the wizard. Then pick up the voodoo doll
of the king that pops out of the cabinet.
Then have Dwayne/Oups pick up the elixir. It's the yellow bottle
near the skeleton.
This completes the level. Click the flashing "Go" in the window. Make a note of the code in the bottom-left of the screen ( ), then click anywhere to continue to the next level, The Wizard's Graveyard.