A few months ago, China announced that they’d be cracking down on exploitative lockboxes found in certain games. If a game features something you open, that then rewards you loot (say League, or Hearthstone, or Guild Wars 2), then that game’s Chinese version must then reveal your odds of getting stuff.
League of Legends is one of the first game to unveil its secrets. PCGamesN has the full translation, but the rarest loot seems to have about a 2% drop rate. Of course, there’s always the possibility (and it’s quite a likely one) that the boxes will have slightly different drop rates depending on the region, but at least this gives you a pretty good idea of what to expect in general.
Expect other games to start rolling out that information next week. I’m especially curious about games that have some form of bad luck protection, like Hearthstone. If you open up enough Hearthstone packs without finding a legendary card, you’ll get one automatically. I’m curious if the mechanics behind systems like that will be revealed, or if games will just be required to unveil its base drop rates.