Board Thread:Ask the Staff/@comment-27065637-20151107203749/@comment-25044056-20151113051909

I think the number of arms has something to do with how the members of the fusion feel about each other. Garnet, Rainbow Quartz, and Stevonnie all have 2 arms.

These fusions weren't formed for the sake of power; Garnet and Rainbow Quartz were both formed for the sake of intimacy, while Stevonnie spontaniously forms whenever Steven and Connie are dancing together. I think if a fusion is between 2 people, and at least one has romantic feelings for the other the fusion will have 2 arms.

Rainbow Quartz is more unstable than Garnet because Pearl's feelings for Rose were not mutual, she lied about her reasons for forming Rainbow Quartz, and her desire for intimacy was mixed with jealousy and a desire to spite Greg.

Opal, Sugalite, Sardonyx, and Malachite were all formed to gain some sort of physical or tactical advantage.