Well you can stop him first turn, but it requires you to get lucky. I’m unaware of a hard counter. You’d need a combination of an Empowered mana generator (dumb luck with 4-matches notwithstanding):
- Princess Elspeth
And a non-targeting spell counter:
- The Silent One
- Emperor Khorvash
I don’t think there’s a hard counter if the gems don’t fall in your favor.
Generally I just plan to let the Fox cast. Since his spell has a known effect on the board, you can try to clear out a match that would cascade after he casts. Doesn’t always work, of course.
Spirit Fox is weak to summoning teams.
Like Astral Spirit, he can only ever damage the top troop, which can be a disposable unit if you employ summoners.
EDIT: My stupid is showing, sorry.