Like many Klei games, Invisible, Inc. is a mashup of genres and ideas in order to deliver something unique. And like many Klei games, it often falls just short.
Invisible, Inc. is part roguelite, part stealth game, and part XCOM. It actually reminds me most of FTL: Faster Than Light in terms of its overall game loop: each run involves you selecting from a number of possible missions which deliver random but predictable rewards.
You're under a strict time limit so you can't do everything, and this restriction forces you to come up with an ideal team composition using only the cards you were dealt.
At its highest points it makes you feel like a genuine spy and delivers all the tenseness and stress of a good spy thriller. At times you'll feel like a complete genius; thanks to its turn based nature you're able to perform some really neat feats that Sam Fisher would never be able to do
But the more you poke and prod at the game and its rules the more disappointing it becomes.
Missions and levels are procedurally generated, but they do little to hide the flaws of this approach. Nearly every level contains at least one hallway to nowhere, or an empty room guarded by a stationary guard facing a wall, or two doors next to each other leading to the same room (and one of them is locked but the other isn't)
There are several types of missions, but they all boil down to the exact same thing: enter place, sneak to mission device, interact with mission device, leave. The game does very little to mix this up and hopes that its procedural engine is able to generate enough micro stories to fill in the gaps.
The one exception to this is the final mission. Like FTL the entire game is leading up to the final mission, and like FTL the mission itself contains elements you haven't seen in any of the levels prior. It can be frustrating, especially as many of the "new" mechanics (like needing to physically hack an object for 4 turns, when all prior hacks are done remotely and instantly) are just clunky ways to increase difficulty
There's a great game waiting to emerge from Invisible, Inc. Hopefully we'll see a sequel one day that expands on what this game started.