Cyberdimension Neptunia: 4 Goddesses Online (EP)

After heading to Wishuel for the first time, you'll be introduced to the guild, which functions similarly to the one in the other Hyperdimension games but is classified by ranks. Initially, you'll only have Rank 1 quests to do. Grab all of the quests and complete them (they're all easy and mostly deal with collecting resources or killing specific enemies). Be mindful that some enemies appear in multiple locations so you can't kill the Goblins in Alph Plains for the quest, you have to kill them in Logi Mountain.

Once you finish all of the available quests (and talk to the NPCs in town), a final promotion quest will appear to defeat the Blitmate on top of Logi Mountain. Clear it and you'll unlock this trophy.

You'll also get the following trophy along the way: