On July 25th 2019, Valve pushed a new patch to Team Fortress 2. With the patch, multiple things were added to the game, such as the Summer 2019 Cosmetic Case, Tournament Medals and some other fixes and updates. What happened next would shake up the global trading community.
With the July 25 patch, Munition Crate Series #1-#18, #82, #83 & #85 became glitched resulting in a 100% unusual drop rate. This way, players that unboxed these crates were guaranteed to receive an unusual item each time they opened a crate whilst the chance of unboxing an unusual is ordinarily around 1%.
Not only people that owned crates from these series quickly rushed to make profit by selling them for heavily inflated prices; there were also people that actually started opening these crates. As a result, the Team Fortress 2 market was quickly flooded with these 'glitched' unusuals, resulting in huge price deflations of formerly quite expensive items; some of the cheaper unusuals that ordinarily sold for around $20 US went for as low as $4 US.
Even when tons of people were Tweeting at Valve, streaming and filing reports of the glitch to Steam support, Valve failed to respond. The glitch was allowed to go on for an ashtonishing 14 hours resulting in cashed out 'glitched' unusuals with which games and/or other in-game items were bought which increased the complexity of the problem.
On July 26th, around 9pm, a Tweet was published on the official Team Fortress 2 Twitter stating that trading, unboxing and marketing for TF2 would be down for a bit until they investigated the issue. A status update was promised to be published a couple hours later. And they did.
4 hours later, on July 27th 1:49am, a new Tweet was published in which an update was given about the unusual situation. 'All unusuals unboxed from 'bugged' crates are marked as non-tradable for the time being'. In addition to that, the TF2 team were said to be evaluating what to do next. A new situation report is planned to come out next week.