Collect 5 rare Gold Rewards. Rewards can be found at any point in the game.

An easy walkthrough for all the Rewards in the Game can be found on this link: http://www.tombraiderchronicles.com/tr7/walkthrough/index.html. As you might already found out, you don’t need to collect all the Rewards in the Game. There are about 68 Bronze Rewards, 38 Silver Rewards and 8 Gold Rewards. So in case you can’t find a Reward, you can just head on and get another one.

After you completed the a level on any difficulty, you can load that level and choose Time Trial. Choose this and complete the level under par-time. If you have a hard time completing those levels on Time Trial, you could use this glitch:

After you died the first level and loaded the last checkpoint, you’re Timer will start. So if you play till the end of the level or just to the middle, you shouldn’t have trouble completing the level before you’re out of time. Though, you’ll have to die at least once to start the Timer, otherwise you won’t get rewarded the Achievement.