The cluster pay mechanism changes up how paylines are created. Instead of 3-of-a-kind from left to right as is the standard, here you need 5 or more identical symbols to create a win. However, while the absolute number is higher, the formation is made easier as all the symbols need to do is touch – either to the side or above one another – anywhere on the grid.
The larger the group of identical symbols, the more lucrative the winning rate. And in this case that means increasingly higher prizes for up to 15-of-a-kind.