To activate the free spins bonus round, at least four Zeus symbols must appear on the reels in regular game play. You will then get 15 free spins to start; with three or more Zeus symbols during bonus play, you can trigger additional free spins. There is no limit to how many free spins can be won during a single round, so when combined with the extensive multipliers at play, landing the bonus round can be an exceptionally lucrative experience. Which is why many players opt to simply buy into the bonus round.
While there’s no official limit on how many free spins you can win during this round, we want to point out that there is a max win allowed per cycle, which is 5,000X your bet.