Item description:

Press continue, and you'll spawn at a mutator hotspot. Move into the house quietly. You are searching for an immobile mutator. He will be medium-sized with his shirt off. He will be lying down or sitting up somewhere (its location is totally random) you have a fully leveled Peggy rifle equipped with high-damaging mods. You can also equip a curveball. You need to agro the mutator while it's in walker form and kill it before it fully mutates. The trophy will pop once you got it. If you mess up, you can reload the save.