At the bottom node I was playing Karn. Due to my Urza-Thassa combo there was a huge blue match across the board (the factory support had 25 shield). When this happened my Castle Vantress landed on top of 2 permanent supports and all 3 had the same color gem. Normally they would change colors but for some reason my board remained empty from the blue matches and the 3 supports kept matching without ending.
Infinite mana sounds sweet but not if the turn never ends. The loop timer kicked in at some point but even when I selected to end it, it kept going.
Aside from the infinite mana bug, the loop timer really needs to be fixed. Either it pops up and goes on like before or it doesn’t come up at all.