Originally Posted by Mordeth_kai
we have been trying to test out this feature and more detailed info on it would be very helpful. For instance:
Can different races work together?
Do the army's absolutely have to be similar strength, if so how similar?
Do both players have to be on the same quest or can a more experienced player help a less experienced player?
Yes, different races can work together - you can be an Elf and invite an Orc player to help on a quest/siege.
Hmm, not sure about the exact strength requirement, it might be something like +/-50%. Edit: Just looked it up, it's +/-70%
Only the player requesting co-op has to be on the quest, the other player could have completed that quest months ago, not be at that quest yet or not even have the option to do that quest (e.g. different race).