Absolute Virtue as my commander, the opponent had a mass token producing deck. It got to the point that their attacking animations took so long with so many tokens that it forced me to concede the game, even though I would have won through their deck burning out first if the game had kept going. Something about the number of triggers and the amount of different attacks slowed it down and didn't allow me to do anything so it timed me out and forced me to concede.