Valve's Dota 2 is a free to play game, meaning a player could download and play the game for hundreds of hours without ever having to spend a dime. The game makes most of its money from in game purchases, including keys to open chests that contain cosmetic items. Some chests contain a huge variety of items, and at $2.49 per key many players were deterred from buying due to the low chance of them getting an item they actually want. Thanks to the latest update that isn't a problem anymore. As of March 20th you can no longer get duplicates when opening consecutive chests. Items you have already received from a specific chest will be removed from the random pool, and you can see what items remain for you in a chest by clicking on it in your inventory. If you want a duplicate (for whatever reason) you will have to have received every item from that specific chest, resetting its prize pool. To celebrate this new feature Valve has added two new chests to the game, each containing four different sets for various heroes, as well as a chance to get a rare set each time you open. If you have been hesitant about opening chests in the past this is a great time to start.
I spent $12.50 on keys the first day of this update and ended up getting two rare sets alongside the five regular ones. I sold one of those rare sets and ended up making $2 overall. Needless to say I'm a big fan of this new update, and I'm glad to see Valve is always finding ways to benefit not only themselves but also their player base.