Regarding the Oxa timer: The portal ores are guaranteed drops, when they used to be random in the last iteration of this event type, I believe. I think players have often said they would prefer guaranteed drops with longer timers over random drops with shorter timers (like Ivy vs Troll Camp in that one common event type). So maybe the thinking on S8's side was along those lines - they made it a guaranteed drop but with a longer timer. The idea seems a good one. I just think they overdid it with the 4 hours. 3 hours would have been much more reasonable, in my opinion.