It's only been one map. Just many versions of it. But me and Chuck have a BTB in the works as well and dues to the aesthetics I added to his base structures, once again they look like cathedrals. I blame the forerunner objects.
Invasion is all the rage lately it seems, but hard to get one that remains challenging yet doable throughout all three phases.
attackers start on asylum area, enters forerunner catacombs which are broesque and goes down into coliseum. trying to balance height advantages and disadvantages with each tier.