Developer 
Features Only Diamonds is a video slot from Gamzix with a 3-5-3 layout, no paylines and no ways to win outside the Bonus Game. The main feature set centres on Mystery, Collect and Upgrade symbols, while two special reel positions keep the highest-value symbols in focus. The game carries medium volatility, a default RTP of 96.01% and a maximum win of 3,500x.
The Bonus Game is triggered by landing any three symbols on the active row or through the Heap of Diamonds mystery feature. It includes three guaranteed respins, with the timer resetting when key symbols appear. Mystery symbols can reveal values from 1x to 9x or trigger total-bet prizes up to 50x, while the Collect symbol gathers all revealed prizes and the Upgrade symbol can raise symbol values by one tier.
Players can use the demo version to play for free and practice before playing for real money. The slot also includes two Buy Bonus options: a standard entry at 30x and a Super Buy Bonus at 75x, which increases the frequency of high-value symbols in the feature.
