|"But the battle is lost!"|
|— Eeltail to Darkstar in Code of the Clans, page 34|
Eeltail is a tom and an ancient RiverClan warrior under the leadership of Darkstar. In Code of the Clans, Eeltail participates in the battle over Sunningrocks against ThunderClan. He is seen chasing away a ThunderClan she-cat who streaks for the ferns under Sunningrocks, with the support of his Clanmate, Blackbee.
When RiverClan is driven away by ThunderClan, Darkstar, RiverClan's leader, tells her Clan that they should continue fighting ThunderClan, and to never give up Sunningrocks. This results in Eeltail deeming that the battle is lost, nodding to his leader that the ThunderClan cats are jeering at them from across the river.
After the battle is continued, Eeltail's Clanmate, Splashheart, sees a ThunderClan cat stalking him, while he is busy trying to hold down another cat. Eeltail lets the cat go. However, in the end, RiverClan reclaims Sunningrocks, driving ThunderClan away.