Girder glitch
From Worms Knowledge Base
This glitch involves placing a girder where not normaly possible, ie: inside the landscape. Use of this glitch is frowned upon in the online community, since placing it over worms will cause them to fall through the landscape and drown.
How to do it
This glitch is accomplished by first selecting the girder and rotating to the way it is needed to appear. Then selection of a homing weapon, of any kind, and a left click (where you want the girder to appear) is needed. Next the drill needs to be selected. Finaly press F7 and Space at the exact same time. A girder will appear where the homing weapons target was.