The main, side, and extra decks aren’t currently the ones I was using game 1 in ranked.
Bug reproduction steps
I was testing out Virtual World in a private lobby before going into ranked. I chose to use Thunder Dragon instead of VW. Game 1 went normally until I had to side for game 2. My main, side, and extra deck were all the Virtual World list. I just clicked “finish,” which then prompted an “invalid deck” message and then my opponent and I had to wait the entire 2 minutes 30 seconds for the side deck timer to end. This happened after game 2 as well since we went to game 3. Probably the best way to attempt to replicate this is go into a private game vs AI, then leave after the game ends, then play in ranked with a different deck.
Thanks for the report.
We are unable to reproduce this. If you have exact steps to reproduce the bug, then tell us.