The Egyptian adventure theme runs right throughout this online slot game, including through each of the reel positions on the main game board. The game takes place against the backdrop of an Egyptian temple – perhaps a pyramid wall, comprised of four rows running across the five reels. Each of the symbols on the reels is styled according to the theme, from the stone-carved high card symbols to symbols like the sphinx, the camel and the magnifying glass.
There’s a wild symbol in Hidden, and you’ll know it when you see it – it’s hard to miss. The bright orange symbol acts in the usual way for a wild, so if it falls in the middle of a payline combination, you’re paid for your win as if the wild was the missing symbol. This also applies to extending combinations, and where a wild falls at the end of a combination, you’ll be paid as if it was one symbol longer. The only exception to this rule is that the wild doesn’t substitute for the scatter, although that’s fairly standard practice for online slots.
The scatter symbol in Hidden is the magnifying glass. When you land three or more of these symbols on the reels, you trigger the main bonus feature – Treasure Room free spins. It is also possible to add more free spins during this round, with one extra free spin added for each additional magnifying glass appearing on the reels in the free spins round.
As with all slots developed by Elk studies they all have great bonus rounds such as Hong Kong Tower and Sam on the Beach with Hidden being no different. The Treasure Room free spins bonus is the main feature, and three or more scatters instantly triggers this round. Here, players are awarded five free spins, which commence immediately after the winning spin. While some games offer more free spins in their bonus round, there is an added twist in Hidden that paves the way for bigger winnings.
During the free spin bonus feature, one of the symbols is chosen at random to form a 2×2 square icon, effectively taking up four reel positions instead of one. These symbols also fall away when combinations are creating, leaving vacant reel positions to be filled by other icons, and thus creating the potential for multiple wins on each bonus spin.
There is also another random bonus feature, which can be awarded without rhyme or reason at any point during the game from the main reels. Known as the Flashback Spins feature, you pick up a full wild reel, complete with 3 free spins to try your luck. The wild reel is particularly helpful for completing paying combinations, or for extending winning combinations by one symbol.