Tom Clancy's Rainbow Six: Vegas
This game is a lesson of game design and level design. It's excellent, despite being too hard and having some bugs.
I've never played an FPS as hard as this. I must have died 100 times in my first campaign. In hindsight, Halo 2 legendary suffers from a rushed development cycle and a scope which was beyond the studio's capability. Rainbow Six Vegas has an AI that is too good at killing the player. The AI knows how to use smoke bombs, flash bangs, flank and defend their positions. To play this game you must look for opportunities to flank, to use grenades, to enter using the backdoor, etc. The level design is great in always providing a secondary route for every part of the level. Compared to Gears of War I'd say that Gears is much much easier than Rainbow Six. Some of the levels in Rainbow Six have traps and you have to be careful.
The opera house at the end of mission 5 almost made me quit. It's mission impossible. I've tried placing the NPC at multiple spots until I've found that if you take cover behind the right box and leave the NPC taking cover at the left box. That's the best case scenario. I didn't use the turret because when I did I couldn't survive the onslaught. The NPC's AI is very good at taking cover and firing at enemies. This somewhat balances out the excessive difficulty of this game. Choosing the best position for you and the NPCs is crucial to complete the missions. It's also crucial to choose how to invade when you place the NPCs next to a door.
Near the end of the game, when you have to hack another system and defend your position from waves of enemies. I must have failed that part dozens and dozens of times without knowing what happened. It must be a bug. I've came to learn that you can't leave the area, because if you do the antagonist flees. Multiples times I've failed without me or the other NPC dying.
Pathfinding is flawed in this game. Sometimes they stay behind cover and you have to go back to mark another point near them for them to leave the cover. In the Dam mission I once had to reload the checkpoint because the NPC got stuck behind an opened door and the door refused to close because the NPC was also blocking it. In some scenes I could use the scope of some rifle to headshot enemies, while the rest of them would just stay put without returning fire. You can hear them talking about the death of their comrade but they don't take action. Sometimes the enemies get stuck behind a cover and the next wave of enemies isn't triggered because of this. You have to find and kill them to trigger the next wave.
I don't know why aiming in this game is so hard. At first I suspected the mouse and some setting, but it's the game itself that makes it hard because every other game has no problems with aiming.
