Zombie Army Trilogy
68 Achievements
1,000
40-50h
Got your back
Helped out companions under direct enemy attack at least 50 times
15
5.46%
How to unlock the Got your back achievement in Zombie Army Trilogy - Definitive Guide
If you are in a room where someone is downed by a crowd and you happen to have a shotgun/preacher, kill everything around them. The achievement seems to count any zombie near a downed player (since they all gravitate towards a downed player for a few moments and that apparently counts as attacking.)
You must kill fifty enemies attacking a coop partner.
This can be boosted easily by letting one straggler live, have it attack your partner then kill him.
I wouldn't worry about boosting, as me and my friend both had it half way through our second run (1x sniper elite, 1x collectible) without having even touched the horde mode.
For this trophy you must kill 50 enemy zombies that are actively attacking your co-op partners. This will most definitely come naturally as you play Horde Mode and can be done with only 2 players, just make sure you stay in close proximity to your co-op partners so you can help them fend off any enemies close by. Zombies will also attack your downed co-op partners. This makes for an easy opportunity to gain progress for this trophy, just kill them before you go in and start reviving your partner. You will receive periodic progress updates on the number of revives you have performed, however, unfortunately you cannot track this in the Career Stats menu.
*ONLINE REQUIRED*
You will need to play co-op modes for this. Just kill zombies attacking on other players. You could boost this if needed having your partner purposely take hits from enemies.