What happened?
I'm not entirely sure myself, but here's
what I think I know happened from what I read.
Jagex released two treasure hunter promotions/deals at the same time. Something with oddements allowed players to get an infinite amount of TH Keys as they were severly cheap from doing so.
Players found out about this and slowly it spread. Around 4,000 accounts took part. Jagex then banned X amount of accounts for 'bug abusing' or taking advantage of what wasn't a bug, but obviously not intended gameplay - It was an oversight on Jagex's part.
Jagex are now admitting that it was their fault 😂😂 Oh, and now the RS3 Reddit is once again in uproar of MTX, because the last ten MTX uproars solved anything.
Also...The link above gives a basic read of what happened. Jagex dummy thicc