Hey all,
@icy is correct, after the current Campaign ends the next Tower of Doom event is Purple and then following the next Campaign it is currently scheduled to be Brown!
But there isn’t a bug here, Tower of Doom events now only run between Campaigns.
At this stage we do not have any changes to include these Doom troops outside of ToD events or change how often they run but that doesn’t mean there couldn’t be special events in the future where this could differ.
This schedule is the same across PC/mob/XBOX/PS.