Killer slugs devour my garden

At this time of the year after a rainy day my garden is invaded by killer slugs that devour everything - my plants and each other.

They hide under the rhubarb leaves and in the chives.

Killer slug.

I do my best to exterminate the slugs but its a tedious and unpleasent task.

What is the most efficient way to get rid of the slugs? Preferable not too toturious to the slugs or poisonous to the garden??

Here are a few methods that require less work than handpicking the slugs:

• Use beer to lure the slugs. Put a cup or jar with beer in the soil. Once the slugs fall in they will die from drinking the beer or simply drown.
• Use cornmeal to lure the slugs. Put cornmeal in a jar and lay the jar on its side. The slugs crawl in, feast on the cornmeal and die. 

Because the slugs die in a container it's easier for you to dispose of them without getting slimed!