[Norfleet]

Originally posted by Master Shake:
1. the new Global attempt to replace a random existing global, with a comparison of gems input and die roll?

Yes, although I would say that a "random" global is attempted, rather than a truly random one.

2. the new Global attempt to replace the global with the minimum number of extra gems?

This doesn't appear to be the case, I have not noticed any such determinism.

3. the new Global attempt to replace an enemies Global first?

No...in fact, I think the attempt preferrentially attempts to replace your own globals first, just often enough to be suspicious, but not often enough that it is demonstrably intentional. This is another example of hidden developer sadism at work.