Earth Defense Force: Insect Armageddon

There are portions in the game where you'll be able to drive a tank against the Ravagers. You may be able to get this trophy on your first playthrough if things go favorable, but expect to play at least two rounds to get this. The tank, although strong, can only take so much abuse before you are forced to abandon it.

Best place to grind these kills is in Survival mode. The maps Double Whammy and Original Sin both provide you with a tank right at the beginning of Wave 1. Grind your kills here. If the latter waves are too tough just repeat Wave 1 until you've reached your 500 kills.