Designed and illustrated by Brandt Brinkerhoff, and published by Lucky Duck and Aesc Games, Oros is a world-building game where players represent primeval demigods who are shifting tectonic plates in order to raise mountains where they can send their followers to build temples.
The core mechanic for Oros is worker placement: you'll be sending your followers to action spots on your individual board in order to take the action indicated, and each turn you get to take three actions. Among these actions will be those that alter the game board: a shift action slides an entire row or column of tiles; a move action moves a group of tiles, and if that results in tiles colliding, then that could result in the creation of a new mountain. Moving tiles can also result in new volcanoes being added, and as an action you can cause a volcano to erupt, which in turn will add to the land mass. If a suitable mountain location is available you can send a follower to build a temple. You can also, as an action, send a follower to study and you can take an action to return them from study; the latter will give you wisdom that will enable you to advance the tracks of any of the actions and so strengthen that action the next time you take it.
When you send a follower to take an action, you can't repeat that action until the action spot is vacant. This is an interesting device that makes Oros something of a puzzle-optimisation game but it can slow the game down as you'll often have to wait longer to take an action than you'd like. Turns can be slow too because, by definition, the game is played on a board with a constantly changing state. That means it can be hard to plan your move while you're waiting for your turn because the board may have changed significantly by the time your next turn comes around.
Nevertheless, we've enjoyed our plays of Oros. The mechanics are interesting and feel commendably fresh. It's fun manipulating the board by crashing land masses together to raise mountains and by using lava flows to spread a land mass, and there are some meaty decisions to take about how best to utilise the 'wisdom' that you earn. The game is also highly interactive, including through opportunities to block players off from using locations unless they've unlocked the action track that allows their followers to share a space. There can be advantage in accelerating up just a couple of tracks, especially as getting to the top of a track gives you an added movement on the ascension track that will ultimately determine victory. However, the game also incentivises players for upgrading the action tracks equally as that unlocks additional followers... Likewise, in the mid-game there are likely to be choices to be made about where best to site your temples; players can share the same mountain (ie: players can build temples on the same mountain) but you cannot build a temple on a mountain where you already have one of your temples. That means it's quite likely that players will end up sharing some locations; but when you build a temple on a mountain where another player already has one of theirs, they benefit by earning an extra wisdom...
Oros is notionally suitable for 1-4 players but playing solitaire or with just two players you'll be using a seemingly rather random automata. You may find the game too slow with four players, so, for us, Oros is at its best as a three-player game, which you can expect to run to around 90 minutes.