Tactical cooperative game based on Aliens movies, where you control squad of colonial marines and complete various missions - either in campaign mode or as oneshots.
No matter the mission, you always face swarm of aliens - really hordes of them, Zombicide style. However they get deployed as hidden signal tokens, and you get to know how many of them are in this swarm, only when it enters your line of sight. It is thematic and adds a lot of tension: how many enemies are lurking behind the corner?..
By the way, while aliens miniatures look cool, they require assembly, and are fragile, tails especiall prone to breaking. I would prefer much standard plastic minis instead.
Core gameplay is very simple: your characters can move, shoot, interact, rest and build barricades. Most of them time you just move and shoot. When shooting, you roll d10, and hit if result is lower than your character`s accuracy. Which lowers each time you shoot, and recovers only next turn - another thematic touch.
It might seem that picking (there are characters with various abilities and weapons to choose from) guns which can shoot a lot of times, like smartgun, is the best option, however each shot also discards a card from endurance deck. It has a lot of useful items, harmful events, etc, and also serves as common hp pool: if you run out of it, you lose. This way stronger weapons are balanced.
Speaking of hp, aliens do not have them: 1 hit = dead alien. Do not worry though, game is far from easy as there are always a lot of his brothers around to replace him. And marines have just as much health: 1 hit = downed marine, and if it starts alien turn next to aliens, he gets dragged away. Hopefully you will be able to do rescue mission and save him, if you play campaign mode, otherwise tough luck.
So as you can see, game is really thematic, which I appreciate. You really feel like in action movie, running and gunning horde of aliens.
On the other hand, game is really simple, perhaps even primitive. There is not a lot of tactics: you mostly just shoot whoever you can. Some positioning is possible - so that aliens face your overhelming firepower from optimal position, and you need to be somewhat careful about running out of cards, but overall Aliens are not much different from Zombicide in terms of depth. It is very random (so dice dependent) as well, and there are a lot of minis to manage, place and remove, too.
So if you want really thematic coop, or you are fan of the movie, this is a great choice. If you want more or less deep tactical shooter, better to look for something like Galaxy Defenders or Fireteam Zero, etc.
P.S. As for solo, sadly you still have to control 6 marines. Yes, you can replace most of them with grunts - simplified versions - but that`s still a lot of characters to manage. Too much, imho.