The Diamond Casino Heist is the most involved and difficult task to pull off in all of GTA Online. If you want to get your team out with the most cash possible, make sure you follow these steps.
Just like a true heist, the Diamond Casino Heist in GTA Online will take a lot of prep work to pull off successfully. You and your team will have options at nearly every stage of the heist to determine how it will all play out, and your choices can drastically change how much, or how little, of that sweet loot you end up walking away with. If you manage to walk away at all.
The Perfect Diamond Casino Heist Setup and Approach In GTA Online
Master The Setup
You, or at least one of your friends, will need to own an Arcade to even get access to this heist, so make sure you have that ready first. Once you do, you can enter your arcade, watch an introductory cut scene and get access to your first mission via the laptop. This is a nice warm up mission where you just go out to the Post Op Depository, steal a truck, and haul it and its cargo back to the arcade.
Having done that, the real setup begins with scoping out the casino. This entire section is optional, but you'll want all the intel you can get for this heist. You start out by finding as few or as many locations you can access the casino through, points of interest in the casino, and points of interest in the vault itself.
There are six access points to the Diamond Casino you need to photograph. These are the Main Doors at the front, the Side Doors to the left and back of the building with keypads, the Roof Terrace has four more keypad doors, the Security Tunnel underneath the nearby racetrack, the Roof itself has two keypad doors by the helipad, and the Sewer Tunnel which you enter across the street.
Inside you're snapping pictures of the security guard near the front desk, the keypad to the restricted access doors, a security camera on the ceiling of the main casino floor and on the roof, the valet out front, and the vault blueprints in the manager's office.
Finally you will examine the inside of the vault through various camera feeds on a limited time, so hit all these spots as quick as you can. The first is just looking at feed of the room with the carpet floor, switch to the grey room and find the metal detectors, switch again to see the security office door, find the staff elevator on the right side of the purple casino area, and finally look at the blue door on the left in the hallway.
If you manage to spot all these areas in the setup, you will be able to purchase some useful tools for the heist itself. The casino model will highlight all the access points you found, the door security lets you practice the hacking minigame to break in, and the vault door does the same thing but for breaking into the vault.
How To Approach The Heist
You have three main choices for how you can approach taking this heist on: Aggressive, Silent and Sneaky, or the Big Con. Each have their own setup missions, but all have six that are mandatory and seven optional.
You probably already know if aggressive is the approach for you just based on the name. This method is all about blasting your way through the casino guards, blowing the vault door open with explosives, and then fighting off the cops as you make your escape.
The Big Con is your middle ground between the aggressive and stealthy options, and plays out a lot like you would expect a heist movie to. You start out sneaking in, using disguises and subterfuge to gain access to the vault before you drill your way in, bag as much loot as you can fit in your bags before a timer runs out, and then either sneak or shoot your way to your getaway.
Silent and Sneaky is the one that will be the hardest to actually pull off from start to finish, but if you can manage has the highest chance of you getting the maximum payout. Again, you know what you're in for with the title. This approach is all about sneaking in undetected, using silent weapons only when necessary, using a laser to open the vault, and grabbing the cash while never getting spotted by any cameras, staff, or security.
Despite each approach having seven optional missions, completing all of them makes them far more likely to succeed since they open up more opportunities for you to pivot and adapt with during your heist.
Finally, invest in your support crew. Hiring a gunner will upgrade your guns you take during the heist, the driver will leave you faster cars for your getaway, and the hacker increases the timer on hacking minigames. You don't need to hire them all, but choose which make sense for the approach you're going for.
Counting Your Loot
The highest potential payout for the heist, on your first run, is around $2 million depending on your approach and how many valuables you loot in the vault, but that's before any splits. You at least have to pay Lester a cut, then any support team members you hired, and any other perks you bought to use during the heist. Then, of course, you spill cash for all the damage you take while running it out of the casino. Finally, you will decide how much you split between your crew of two to four teammates before the heist itself starts.