The term "cluster" comes from English and means something like bundle or group. Accordingly, Slot machines with the cluster pay mechanic are all about forming groups of the same symbols. However, this means that the symbols can be not only next to each other, but also on top of each other. The only important thing is that the symbols are adjacent to each other without any gaps. In most slots with cluster pay mechanics, at least five symbols must be involved in such a group in order to collect a win. The charming thing is that win clusters can occur anywhere and do not have to start on the first reel from left to right.
In cluster pay slots, for example, it is enough to have two vertically adjacent symbols and three horizontally adjacent symbols that together form an "L" shape. As long as there is a gapless adjacency of all symbols, it is a cluster pay win. The amount of the win, as with any other Slot machine, depends on the number of symbols that are grouped together. Tend to perceive such cluster pay slots as a bit more confusing, as the "winning groups" are not always directly visible at first glance. A very popular slot in this category is the Aloha! Cluster Pay slot, which was released by NetEnt.