Is being able to trick it out with a good ol' Code Breaker. Especially the Joker commands (blowing up all cars on screen was a fav of mine) and firing mods (rapid fire RPG and Sniper, for example). I know stuff like that can be done now, but not unless your console itself is modded as well. I'll be keeping my fingers crossed, hoping that one of the vehicle spawn cheats is for the submarine; I'd love to have one in Michael's swimming pool.
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I only used the "Everything Proof" codes after I finished the story, it was all I needed and they were awesome. I wish Rockstar allow such a thing as perhaps a post story reward, even if it was expensive.
Band/Artist I've been listening to way too much: Fallon Bowman/Amphibious Assault. https://soundcloud.com/fallonbowman
I miss those days. I think I've used every cheat device since the early 90's. Always had a lot of fun with them after beating the game legit and sometimes there were absolutely crazy codes. (Especially for the GTA games, seriously... I'd like to know what they were smoking when they came up with codes like monster truck wheels on every vehicle, giant rims, acid trip world, etc. That *bleep* was funny as hell!)
"Fight for them, then, and die for their sins!" -Dracula, Castlevania: Symphony of the Night