I'm a noob too, but i'll toss in my two cents. Be warned: they may not be worth it...
You want to use a 10 watt LED from LEDengin, and you want for only one (ish) to flash a red color while the rest remain on (from what I understand)... And then you want to have the Obsidian 2.
All things are possible, I suppose. However, I presume the 10W LEDengin LED you are referring to is something like this:
Now I'm not sure about the specifications of the Obsidian goodies (no offense Ultra, Deep, Crew, etc., I'm just broke!), but I'm sure with the Flash on Clash option being adjustable the way I've read, you could do that. But for some of the LED's to remain on during the process is additional wiring and components i'm not familiar with yet, i'd imagine.
As for power, the Obsidian probably wont be the issue, it'll be that light. The Obsidian was designed to run and work with Luxeon 3 or Seoul P4 LED's which are 3W, as you are probably aware. So my theory (a noob's theory) would be this: More than 3 times the LED power, more than 3 times the juice. Because you would only want the 10W for maximum illumination, and the soundboard acts as the LED driver in a more sophisticated manner, you would seriously have to adjust something for that board! Because with Lithium Ion, you need to take steps to be safe...
I would say Hello and Welcome to the Forum. Through this forum I've learned what I've needed to build 3 Watt LED sabers, and now 5 Watt LED Sabers, with and without sound (econo and MR sound, not Obsidian). I have now 3 Saber projects in the works, which I'm promising myself to finish before my my fourth.
And I too, leathercraft. I admire your armorsmithing abilities, and raise my rawhide maul in approval in your direction. Perhaps we can fight someday...
...and good luck with your 10W, I expect pictures when you get it sorted...