The bonus game is triggered when you snag three of the bonus scatter symbol on reels 1, 3 and 5. This gives you a free spins bonus with seven free spins to start with, but these can be retriggered. Landing another bonus symbol during the bonus game increases the win multiplier by +1, landing two of the bonus scatter symbol grows it to +2, and 3 grows it to +3. It also provides another seven free spins.