Metal Gear Solid: Peace Walker

• Do not bother trying to S-rank or no-kill missions your first time around. Even then, there is nothing to be unlocked from S-ranking the Main Ops, and only from some of the Extra Ops.

• ESPECIALLY do not stress out trying to S-rank boss fights first time round. Just kill the guys and shoot at the vehicle gas tanks.

• To capture an enemy vehicle, you must eliminate all of its escorts, and then kill or sedate the vehicle's pilot when they stick their head out. If you get spotted, however, you need to damage the vehicle a little until they pop out, but they ONLY pop out when there are no more escorts left. Aim for the red fuel tanks for extra damage.

• How research points (I forget the proper name) work, because it's not intuitive: You have a set amount of points, the number of which changes depending on your recruits. When you set something to research, some of those points are used up, but they are returned to the pool when the research is complete. So it's not like cash.

• You unlock Extra Ops as you complete the Main Ops, at a rate of about 1 of each at a time. Finish them all, they unlock new research topics for weapons which come in VERY handy in the Main Ops.

• You may want to grab a guide for parts of the game, such as which Ops unlock what and
  that final Zadornov search.

• Finishing a certain project that you get after the first big (BIG) boss battle unlocks a lot more than you might think. To do it, you'll need to get scrap by blowing away certain parts of bosses, and programs by NOT shooting the big red target.

• Do Outer Ops after you snag a few vehicles. Having an APC or tank will allow you to steamroll the early ones, and you can snag items or blueprints from them.

• For the post-game bonus bosses (anything with 5 or more skulls), co-op buddies are pretty much a necessity.

• Playing co-op with a high level person will reduce your trip through the story significantly, especially if they have specific gear designed to capture more enemies.

• Capturing vehicles can be a slog early in the game. Feel free to return later with better gear.

• You will unlock higher "ranks" of weapons/equipment after you've found blueprints and met the blueprint conditions. Each rank means greatly improved accuracy/battery life/etc. At the same time, using what you've got will "level up" that specific rank and make it slightly more efficient. Levels are shown as red bars in the Rank icon. Overall there's up to 5 Ranks, each of which can reach Level 3.

• Don't overlook the Analyser. It really sucks at first, but it's the only way to find the higher skilled personnel once your teams are full. While your intel team can tell you how many B-skill soldiers are in the level (found in the pre-mission info screen), it's only an average since their actual skill levels fluctuate. The analyser will tell you if that B-skill soldier dropped to a C, or jumped to an A.

• Getting to the very end is worth it, since it adds a ton of context to Ground Zeroes.