GEM MAHJONG

GEM MAHJONG swaps the usual tile pictures for gemstones: 15 different gem symbols, which the developer says were drawn to be easy to tell apart at a glance. The base rule is mahjong solitaire. Two free tiles showing the same gem can be cleared together, and a tile counts as free when nothing covers it. You work your way down through the stack.

Two pressures sit on top of that. There is a timer. And tiles pass through a slot tray at the bottom of the screen; if every slot fills without a match being made, the level ends. For tight moments there are two extra slots that can be opened, plus four power-ups called Magnet, Sweep, Shuffle and Flip, kept below the tray. The developer does not explain what each power-up does, so neither will we. The layout is portrait and built, in the developer's words, for quick mobile sessions.

Tap or click two free tiles that show the same gem; a free tile is one with nothing covering it. The pair is cleared and the tiles go to the tray at the bottom. Keep working down through the stack before the timer runs out. If the tray fills up, the level ends. When you get stuck, use the power-ups under the tray.

Watch the tray as closely as the stack, since a full tray ends the level even with time left on the clock. If space is running out, the two extra slots can buy some room. Learn the 15 gem symbols early; they were designed to be told apart quickly, which helps while the timer is running.

Gem-themed mahjong solitaire with a timer and a slot tray, in a tall portrait frame. Touch and mouse both work, according to the developer. There are 15 gem symbols, four named power-ups and two extra slots.

Prism Match 3D also feeds tiles into a tray, seven slots wide, with Undo and Shuffle to help. Pride Mahjong uses seven collection spots and three types of bonus.