Eterna Forest is a forest in Sinnoh, found in the middle of Route 205 lying near Eterna City. The Old Chateau is near the eastern entrance/exit of Eterna Forest, which is where Rotom can be found under certain conditions.
Cheryl will ask the player to accompany her when they first reach the forest, in fear of an encounter with Team Galactic. Until the player exits the forest, all battles will be double battles, however Cheryl will heal your party after each battle. She has a level 15 Chansey with the moves Egg Bomb, Softboiled, and Refresh.
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