This trophy will unlock in Act 1: Ashes - Chapter: China Shop.

In this Chapter, you will be up against theBerserker. As you proceed through the Chapter, Marcus and Dominic must lure the Berserker outside by standing in front of doorways, where the enemy will do a charge attack. The player must dodge to the side just before being hit by the attack, and the next area will be unlocked. Simply repeat this a set number of times until the Berserker is finally outside of the Tomb. Once theBerserker reaches the Outside, use the Hammer of Dawn to penetrate his tough armor, which may take several rounds depending on the difficulty. After enough rounds, the Berserker will die, and the trophy will pop.

This trophy can only be unlocked in Act One - Ashes  -  Chapter: China Shop.

After the cutscene, you will find yourself in a tomb, trapped under rubble, and with a monster inside with you. After a while, you will encounter the Berserker, an invincible beast that cannot be killed with regular bullets, only the fire from the Hammer of Dawn.

To complete the section, you will need to bait the Berserker to rush towards you at the wooden door. If done correctly, it will be destroyed, revealing a path towards a new room. Repeat until you reach outside, where you will be able to use the Hammer of Dawn on the Berserker.

Once defeated, a cutscene will play out, and the trophy will pop.