Widowmaker event and new hero-
Until now, nearly every character has had a very unique skin to each event. The only one that has lacked the most in terms of character design is widowmaker. Why would blizzard avoid widow maker skins in other events, and for example give reinhardt multiple skins? There's a good chance that its an indicator of widowmaker being at the core of the next event. What kind of event is it? We'll have to wait and see. The next event will likely not start and will not be announced for a few weeks.
Some have pointed at this picture as a representation that a new hero will be a currently unnamed quadraped codenamed Anchora. At the current time its clear that given posts by the overwatch development team in blizzard forums, that 24th hero is on their mind. They have also posted a story of Efi Oladele, an 11 year old AI and robotics genius from Numbani who just had her town pummeled by . Overwatch has been relatively light on villains, and to drive the story forward additional details about villains are needed. Additionally the game is relatively tank light given the 3 tank meta. It would make sense to have a new tank coming.
The Overwatch ARG, (alternative reality game) also ended with a website,volskaysindustries.com, but no actual full resolution. The ARG may be pushed forward again. While its still not clear if clues have or will be put into the new content. The hype over continuing the arg is an interesting question that remains unresolved.
Overwatch League and Combine-
Another major rumor is that the first steps towards the Overwatch league will be made soon. Rumors are that originally it will have less than 12 teams from NA and EU. Each team will be associated with a city. The major concern being from pro players being on how players will be chosen for the combine and from there for the teams. There are different thoughts on how this should occur. One thought is that the players will all compete in a player pool to be seeded onto a team from management. A second approach could be that players will play at the columbine, following will have a draft. The third approach is that the combine will have preset group of 6 players that will compete to be seeded as an entire group. The third approach may be preferred by the organizations which have contracts with players already, while the other two may be preferred for undiscovered talent. Currently, clear combine plans are the most pressing concern for players and likely will be the core of the announcement made.
The second aspect expected to be announced is the Overwatch client side adjustments to make team micro-transactions and paid replays available. This system likely will provide a basis for investors to see the current stability of the system and what direction Blizzard ultimately will take. This could be a first glimpse at the progress that blizzard is making on its replay and demo system. It could also be ways to support a team, and idenity within a region. The first year of the Overwatch league is not expected to be global.
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How these two aspects come together will define the future of the game and give us an idea what to expect.