Resident Evil: The Darkside Chronicles

This is story-related and cannot be missed.

You will earn this in the final Game of Oblivion chapter (the Resident Evil CODE: Veronica storyline).
The ‘queen ant’ is Alexia Ashford, the woman who’s brother you’ll become well-acquainted with earlier on in the scenario. As a final showdown, you must defeat Alexia in her mutated form. In the first form, go trigger happy and keep shooting to weaken her. Be careful when she picks you up; this is when it can get very dangerous.

In the second form, watch out for the tentacles, fire and ants, and keep shooting. Once again, if she picks you up, unload all you’ve got, or you’ll suffer massive damage. You'll travel along a nearby catwalk, but that doesn't mean she'll stop attacking. Watch out for the tentacles and fire blasts. Soon enough, you’ll pick up the linear launcher. She’ll grab you, but just shoot her with your new firearm. Now, in the final form, things calm down. Keep whittling away her health, and soon enough you’ll be prompted to shoot her with the linear launcher again. Then, the Game of Oblivion scenario will end, and you’ll earn the trophy.

IMPORTANT NOTE: I highly recommend stocking up on ammo for this fight, as it's easily the hardest boss in the game. On my first try, I had roughly 100 bowgun ammo, 150 submachine gun ammo and 20 shotgun shells, but it was still not enough. You'll find yourself in quite a mess if you don't have enough.