Corpse Bags are a type of item typically found left behind by a deceased player.
Corpse Bags are also occasionally found inside of Presents sold by the Ghist Shopkeeper, where they contain 12 bombs and rope. They will always be yellow bags, the same color as Ana Spelunky's corpse bag.
Completing the Sun Challenge will also prompt a Corpse Bag containing 24 bombs and 24 rope to spawn near the entrance, with the same color as the player that initiated the challenge.
Corpse Bags may be cloned using the Clone Gun, and copies will store the exact amount of bombs and rope that the original contained. A common strategy is to bring the Clone Gun to the Sun Challenge in order to clone the reward bag, netting a single player 99 bombs and 99 rope, so that they may be used in the Cosmic Ocean.