Mr. Snake's from Dreamwork's Bad Guys, Serperior, Seviper, Ekans and Cucco are respectively from Nintendo's Pokemon and Legend of Zelda and this screenshot's taken from Valve's Garry's Mod.

This giant chicken was wondering around and just spotted these four snakes on sight and is like "Ooh, wormies." Then, Serperior notices it and calls out "All unit, slither!" and they begin doing so out of here for safety, avoiding being swallowed by it.