With the Emerald Driver 4 channel you will get damn near EVERY color under the rainbow.
Literally
I've seen people do some crazy stuff with it! You can even program a "flicker" effect, though I'm not sure how. You're gonna want to ask someone who owns an Emerald saber...
Right, it's called "Pulse Mode" and it's a function that changes between two colours within a specific time frame - which can be set from very small (fast movie-like flicker) to very high (slow transition between the two colours). You can use it with any colour combination and with both Drivers. In the case of the 2-channel Driver the colour combinations are restricted, obviously.
You can check the videos from Emory about the Driver
here and you can also post your questions in the forum, of course