Is umbreon worth it in flareon decks.

I'd say probably not. It is pretty matchup situational, it can be good on gardevoir if their board is vulnerable, but I would just reccomend running a gravity mountain instead. (maybe.) I would run a leafeon instead probably because it negates spread damage, and helps you with the grimmsnarl, zoroark, and charizard matchups. Also if you go aggressive out of the gate with flareon, you can force them to respond with driffloon, with requires them to play a lot of energies, which can power up leafeon's first attack, potentially leading to KOing a gardevoir. yes, umbreon can one shot mew and latias, but leafeon can too. 🤓