This is a phrase I picked up from the duckfeed.tv boys to indicate a strategy that feels, perhaps, counter to the spirit of the game. I would more narrowly define this as “an action that takes advantage of a game’s design in a way that was likely not intended, and would not work more than once against a human opponent”.
My most recent example is in Heroes of Might and Magic 3: The Succession Wars. I am currently facing an army that is an order of magnitude larger than my own - I have no way of even scratching them in a fair fight. So instead, I have been taking a hero with a single black dragon, charging at their castle, then casting the Armageddon spell (which massively damages every creature except my black dragon, whomst is immune to magic) and running away. I then rehire my hero and do it all over again 2-3 days later. It costs about 4500 gold per attempt but it’s costing them waaay more.
And of course, this would not work against a human because they would just take their massive army out of the castle and wipe me out. Which is still a risk here, BUT much less so because the AI is pretty darn stupid.
Another example is, IIRC, from Red Alert 2. The AI tends to highly value destroying ore trucks, and I remember driving ore trucks around as decoys so that I could get all their units in a small area and then surround them. Stuff like that.
On the other hand, I wouldn’t count something like “using the same move over and over in a fighting game because you know your human opponent can’t handle it.” This is annoying, sure, but it’s a valid tactic that your opponent can overcome with enough practice.
What’s your favorite depraved gamer tactic? I wanna hear how you exploited weird edge cases in games.
EDIT: changed to Depraved because shnozlak rightly pointed out the previous word choice sucked