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Online slot machines with abstract themes and symbols can become pretty successful, with Starburst from NetEnt being a great example of a game where the symbols are mainly just colorful crystals. Playtech now have their own, err, spin, on things with Upgradium: a 5-reel, 25-line game where strange shapes and magic minerals are all we see on the reels. Like all games from Playtech, it manages to look quite impressive with its sharp graphics, along with plenty of color. A tinkling soundtrack plays along as the reels spin, which adds to the likable nature of the game. Games developer Playtech is one of the biggest names in the online and mobile casinos business, with most players being familiar with the range. Like all of its games, Upgradium is a slot that can be trusted to deliver fair results, with each spin being determined by Random Number Generator software to give us a high return-to-player percentage. Add to that the 40 paylines and great graphics, and you have a unique slot game that you will not forget any time soon after you have played it! The list of games available from developers at this casino is like a whos who of the online slots industry.