Overview:
-Estimated achievement difficulty: 4/10
-Offline: 33 (1250)
-Online: 0 (0)
-Approximate amount of time to 1250: 17-18 hours
-Minimum number of playthroughs needed: 3
-Number of missable achievements: None!
-Glitched achievements: None!
-Do cheat codes disable achievements?: No!

This Road Map will lead you to 1000 on Tomb Raider Legend as well as the extra 250 if you decide to purchase Tomb Raider Anniversary as DLC. To get there, you'll have to do 3 playthoughs: 1 normal Legend playthough, 1 time trial Legend playthough, and 1 Anniversary playthough. As you're doing your first playthrough on Legend, take some time to familiarize your self with the routes you should take or any tricky puzzles and their solutions so when you perform the time trials, you'll know what to expect. When you complete time trials, you'll unlock cheats that you can use to make the speed runs much easier. Here are the useful ones:

One Shot Kill: Complete Bolivia Redux time trial (Hold , press )
Bulletproof: Complete England time trial (Hold , press )
Infinite SMG Ammo: Complete Peru time trial (Hold , press )

Step 1: Croft Manor
You'll want to start off at Croft Manor, the training level, first. Not only will this level teach you about her gadgets and moves, but it also contains some rewards that you'll need as well. When you're ready, pause, save your rewards, then exit the manor.

Step 2: Legend Playthough (On Tomb Raider difficulty)
Start up a new game on the "Tomb Raider - Hard" difficulty. This playthrough is simply getting through the game on hard and getting most of the rewards. Have the list of rewards available do your best in getting them as they come up. You do not need to get all the rewards to gain the achievements; you just need 60/68 bronze rewards, 30/38 silver rewards, and 5/8 gold rewards. If you feel a certain reward is too tough, just skip it and hunt down the next one. By the end of this run, you should have all the level related achievements, all the reward related achievements, and the two achievements for completing the game.

Step 3: Legend Time Trials
From the title screen, select Load > Replay Level. The time trials do not have to be done in order, so select whatever level you want to tackle first. I highly recommend starting with Bolivia Redux as that will unlock the one shot kill cheat that will help on the other time trials. When you're on the mission prep screen, scroll down to difficulty and change it to 'Time Trial.' When you're doing these, always try to think of what you need to do next. Move efficiently and try your best to avoid dying or falling.

Step 4: Croft Manor Redux [1250/DLC Only!]
Start up Tomb Raider Anniversary from the main menu and head back to Croft Manor and complete the tutorial there. If you've just beaten Legend, this should be a piece of cake for you.

Step 5: Anniversary Playthough (On Hard difficulty) [1250/DLC Only!]
Start up a new Anniversary game and make sure to be on the Hard difficulty. If you played the original Tomb Raider, this should be very familiar to you. There will be less action and more puzzle solving compared to Legend so bear that in mind. Fortunately, there are no speed runs to worry about here so take your time and be sure to get all the artifacts/relics as you progress.

Conclusion
As you play through Legend and Anniversary, the achievements should come naturally. The only thing you need to pay attention to are the rewards/artifacts/relics along the way.

[x360a would like to thank jukkakhan for this road map]