Gnome Chompski

Gnome Chompski is a garden gnome exclusive to the Dark Carnival campaign. He made his debut in Valve's Half-Life 2: Episode 2 and is infamous for earning you the achievement "Little Rocket Man". In the Left 4 Dead universe, he can be picked up by scoring over 750 points in the shooting gallery minigame at the fair and must be taken all the way to the Rescue vehicle to unlock the "Guardin' Gnome" Achievement. All players within the entire Dark Carnival campaign play-through will attain the achievement, dead or alive, so long as one Survivor makes it into the rescue chopper with Gnome in hand.

Trivia

 * Gnome Chompski also makes a cameo on Valve's Portal site during the Christmas holidays.
 * Gnome Chompski is visible on the campaign poster for the Dark Carnival campaign, on the ground behind Ellis.
 * Gnome Chompski may be a reference to the Travelling gnome prank, where people steal garden gnomes often with the intention of taking pictures with/of it to send back to the owner.
 * The name Gnome Chompski is likely a reference to political activist, author and linguist Noam Chomsky.
 * The Gnome is exactly 48 inches, or four feet, tall (hat included) making it actually shorter than the required height to go on most of the rides. Ironically, the Gnome is too short for the merry-go-round but tall enough for the roller-coaster. It might be a hint, that the Survivors walk over the roller-coaster but not over the carrousel itself.
 * The Gnome achievement to save him from the second map of the second campaign, Dark Carnival, is based on the Little Rocket Man achievement to carry him all the way through Half Life 2 Episode 2 and launch him in the rocket that closes the portal from the Combine Overworld.Or it could be a reference to the survivors,because 2 + 2 equals 4 (4 survivors).