You can win the game on Deity difficulty and score some easy achievements by taking the following steps:

1) Choose your civilization.
2) Create a custom game with only "Score Victory" checked, and change the turn limit to 1.
3) Load the game and choose the Found City option.
4) End your turn as soon as the option becomes available. You win the match, just like that, and you will unlock numerous achievements. This works on any difficulty setting.