We also know that they can summon what appears to be unlimited amounts of troops from the Volcano with no repercussions as these events have been witnessed since players began exploring the regions.
I'd also like to point out that this statement lacks any sort of evidence to back up the "with no repercussions".
Imagine an army besieging a capital and the capitol has 5k cs defenders in it. Then all of a sudden when the turn comes around there are 10k cs worth of defenders. This could be seen as "summoning troops" and there are no apparent repercussions. However, we all know there are legitimate game mechanics behind this. We don't need to actually know how many troops are in a human realm recruitment center to know they have a limit, and neither do we need to know the exact same for the Zuma. They are limited and they have specific things they require.
