This mod is bad. I would give it half a star, but I do think it has some redeeming qualities: the new UI and weapon models are clearly quite high effort and do look very good. The biggest problem with this mod is the fact that there are NO breaks, it is constant combat. Whereas Half-Life is Run Think Shoot Live, Invasion is Shoot Shoot Shoot Shoot. It is absolutely exhausting playing this mod because you never have an inch of breathing room. I didn't finish this mod because I couldn't bring myself to suffer even a minute more of playing it. The least fun Half-Life mod I have played.

When I started this mod, I had no context for it. After I played it, I learned that it's highly regarded as a well-known early Half-Life mod. And that came as a surprise to me, because in my experience this is a steaming pile of dogshit. Dragging Kate along with you is so annoying, not just because the follower mechanics are broken and buggy (although they are), but because she will constantly run into the middle combat and get herself killed, which is a fail state. It is so frustrating to fail because the AI was being an idiot, through no fault of your own. But the biggest fault of this mod is the god awful level design - just endless winding corridors full of locked doors, with no clear direction on where to go and what to do. And it doesn't even look good visually! I guess you should play this mod if you want to experience the early history of Half-Life modding, but there are way better early mods and you should know what you're getting yourself into with this one.

I think most people's issue with this mod will be the combat, but actually, I would say the combat is my favorite part of this mod. I liked mastering the gameplay loop of ducking behind cover, charging your attack, and then popping out of cover to deal damage and recover health. It's challenging in a way that I actually like. The problem with this mod is the level design - there are so, so many times where the game does not communicate what you're meant to do at all. And the new sphere enemies are just not fun to fight, they suck.

Opposing Force is a good game. I don't think it's as good as Half Life, but I do think it's good. I find the story of the HECU - a bunch of (mostly) young soldiers sent into a hellhole without ever being told what they were getting into, and their struggle to survive the Black Mesa incident. - very compelling. I also liked most of the gameplay. But there are definitely some areas with not-so-obvious solutions, especially compared to Half Life. On my first playthrough I got stuck in a few areas, but I've played the game again since then and comparatively breezed through it since I remembered the solutions I struggled to figure out before. I acknowledge the possibility that I'm just dumb, but at the same time, on my first playthrough of Half Life, I didn't really get lost at all, so I think my getting lost must also be attributed to some difference in game design. Some of the weapons are weird but I still like them, although grappling with the Barnacle Grapple can be somewhat frustrating at times. But overall, I would still say this game is quite fun. Not as good as Half Life, but definitely still a worthy entry in the series I would say. Although apparently Valve would disagree if their ignoring of everything introduced in this game is anything to go by.

Oh, and also, the hard mode in this game is true to its name. At least for me it was.

I want to like Blue Shift more than I do, but it's honestly just eh. The puzzles are pretty stupid, especially in Power Struggle. The ending chapter is so, so very boring. And overall the game is quite short, which isn't necessarily a bad thing but Opposing Force having a longer campaign that is also more fun is definitely a mark against Blue Shift. I want to like this game, and I guess I would say I do, but I don't think it's particularly good or fun especially when compared to Opposing Force and obviously Half Life.