So, what, the whole game is about a Weekend at Bernie's-style madcap adventure to pretend Tony is alive? Or is he a zombie?
Neither. In the opening cinematic, you see the finale of the movie. Only here, Tony whirls around just in time to kill his attacker and somehow escapes the mansion entirely unscathed.
"Ha, not this time! I ain't learnin' nothin' about no stinkin' morality!"
So, forget about that whole character arc thing. In the alternate universe of the game, Tony pays no price for his hubris, and so the story is instantly transformed from a gritty morality tale into yet another Grand Theft Auto-type game where you amuse yourself by wreaking havoc, with no consequences.
Man, he's really going to blunt those chainsaw teeth. He'll regret that later.
You also have to keep in mind that the only reason the drug dealers are coming to kill Tony in the finale is because of a good deed he did -- his humanity finally overcame his greed when he refused to murder innocent kids. Yet in the game, putting random civilians in danger is not just allowed --the player is actually rewarded for it. Driving on the wrong side of the road, creating unnecessary explosions and doing basically anything that endangers innocent life increases your "balls" meter.
What? Don't look at us that way. There is an actual balls meter. It measures your balls level.
For destroying balls, you get 30 balls. Game economics.
Anyway, when the balls meter is full, presumably meaning you are at total balls-saturation level, you go into "rage" mode. You become literally invincible, and you have unlimited ammunition. Reviewers absolutely adored this feature, saying it captured Tony's "seeming invulnerability during raging shootouts" in the film.
Tony, being invulnerable.