>>106207757They're painfully codependent. The literally could not stop playing footsie long enough to SAVE SOMEONE'S FUCKING LIFE.
Look back at every cross-gem fusion. Beyond their obvious physical deformities, all of them have some sort of mental discordance as well. Sugilite and Malachite were violent psychopaths, Opal has memory problems. Jasper ended up with an obsessive compulsion to fuse and Lapis got... well, I don't know what the compounded form of PTSD is. Double PTSD.
Hetero fusions -especially those that are prolonged- are clearly not healthy for Gems, even if they are terribly useful in the short term.