The symbols you will land on the reels include blue and red sevens, diamonds, bells as well as low-paying card suites. The wild performs its standard symbol replacement duties. The number of wilds you land on the reels determines the multiplier value you get.
Land at least 3 Bonus (scatter) symbols on the middle reels and you get 7 free spins to start with. As mentioned earlier, the Prime Zone slot enables you to choose the volatility:
Low volatility – Prime Zone covers reels 2-3-3; max multiplier x5
Medium volatility – the Prime Zone covers reels 3-4-5; max multiplier x15
High volatility – the Prime Zone is moving with every spin; max multiplier x20
The Prime Zone is a back to the basics slot and players used to feature-rich games might consider the gameplay off-putting. To cut a long story short, the Prime Zone is a hit or miss. It all depends on what kind of slots you prefer.