28 Minutes Later

28 Minutes Later: Complete the "Outbreak" mission on Normal difficulty before the 5th night.

Worth 10 achievement points. Easily doable on normal, but possible to do on hard difficulty (if you are aiming for the [Army Of Darkness] as well).

There is no set tactics for this achievement although some common rules apply:

1) Use more then 1 attack team during day time. 2) Have a Hellion team scouting and destroying the far outposts and single infested structures, use the infantry to do closest ones first. 3) Assign hot keys for better attack groups management. 4) Do not forget to fortify your base with bunkers, you will have to live through at least 2 nights.