Heist Prep Missions

Let's take a look at all the important prep missions that need to be completed for this approach and how to do them. These prep missions can be completed either solo or with a friend and can be done in either a public or solo session. Although it is possible to complete the prep missions alone, we recommend that you enlist the help of a friend.

Support Crew

Gunman

For a gunman, players would normally go for an expert level gunman here, seeing as the approach is aggressive and requires a lot of combat during the heist. However, that is completely wrong. Do not get baited!

Instead, you can still go for KARL ABOLAJI, who takes only 5% cut. You can also choose the loadout you prefer, either the shotgun or revolver one (although we prefer the shotgun). It won't matter as you will get the SMG with both of them... and you will mostly be using the SMG with the Aggressive approach.

If you choose a shotgun loadout then it will be beneficial in close range combat situations. In our opinion the revolver is not worth it as the fire rate isn't too good given the combat nature of the heist. So you should choose the shotgun loadout which will give you a shotgun and SMG to carry out the heist finale.

Driver

If it was up to us, we wouldn't hire any driver at all since we won't be using the getaway vehicle. Because it is mandatory to choose the getaway driver you can go with the lowest possible driver available to hire which is KARIM DENZ, who takes only 5% of the final cut.

Go with the SULTAN CLASSIC if you do decide to choose the getaway vehicle for your escape. We are not saying you do not need to choose the vehicle at all, but if the vehicle is in a good spot, such as in a parking lot next to the sewer tunnel entrance, then by all means go for the vehicles. Otherwise just get a pedestrian car for your escape. More on that later in this guide.

Hacker

The hacker always plays the most important role in the Diamond Casino Heist. They decides the total time you get in the vault before the alarm goes off. Therefore, we recommend you spend all you have on the hacker and do not hold back. You should choose the elite hacker AVI SCHWARTZMAN if you've unlocked him already. If you haven't unlocked AVI then check out our guide here. Avi takes 10% of the final cut and he provides you with 3 minutes and 30 seconds in the vault.

The default expert hacker you have is PAIGE HARRIS who takes 9% from the final cut and gives you 3 minutes and 15 seconds. So if you do not want to go through the work of unlocking Avi just choose Paige. However, unlocking Avi is totally worth the effort.

Hacking Device

The hacking device mission can be in two different locations. One will require you to get the hacking device from the FIB building while the other will require you to get it from N.O.O.S.E headquarters.

N.O.O.S.E Headquarter's Mission

If you get the N.O.O.S.E headquarters mission, then you will be directed to go to Davis City Hall, take out the corrupt agent, take his keycard and head to the N.O.O.S.E headquarters. Once you reach the HQ, make sure you park your car right outside the entrance of the facility you'll be heading in, since right after you exit out of the facility with the hacking device, you will get a 3 stars wanted level and need a vehicle to get away from the cops.

You need to find the hacking device using your phone, based on the signal strength at the bottom right screen. The closer you get to the device, the stronger the signal gets. It is pretty simple, just avoid the sight of the guards and walk silently and you should be good to go. You can use suppressed weapons to take out guards and security cameras provided that other guards don't see you doing so or find the body of a guard you take out.

FIB Building Mission

Before heading to the FIB building, you will need to take out some agents and get the FIB agent pass in order to successfuly enter the building by impersonating an agent. You will be asked to go to a specific location and kill the agents, get the FIB pass, lose the cops and after that, head to FIB building. Make sure that, just like for the N.O.O.S.E headquarters mission, you park your car right in front of the entrance as you will need to quickly get away from the building. Cops will be on you right away.

Enter the building and avoid the cones of vision as much as possible, since staying in them for too long will cause the guards and agents to recognize you. Take the elevator to the upper floor, bring your phone out and find the hacking device using the signal strength bar, the same way you did when in N.O.O.S.E headquarters.

Once you have acquired the hacking device, head back outside the same way you came in from. But note that as soon as you reach the exit, the agents will recognize you and start shooting, so make sure you have some snacks and armor. Quickly exit the building and get into your vehicle which you parked right in front of the entrance earlier, lose the cops and deliver the hacking device back to the Arcade.

General Prep Work

General prep missions that you need to beside the mandatory ones (Vault Keycards) include doing the Duggan Shipment mission. You can pretty much skip the rest of the General Prep missions though.

Patrol Routes is a debatable general prep mission. This one is completely up to you, but we recommend you complete it as well. Completing the Patrol Routes prep mission allows you to see the location of the guards on your mini map during the finale. Some can argue that we do not need this since we will be going all in guns blazing. But in any case, knowing your enemies location isn't harmful in any way whatsoever. As we said, the choice is completely up to you. You can either skip this mission or do it for your own ease.

You can skip the Power Drills and Security Intel general prep missions as well.

Vault Keycards

There are two possible missions that can be given to you to acquire the vault keycards. In one of the missions you need to hijack a prison bus and head to the prison impersonating a prison guard. While inside, you go to one of the towers, silently take out the guard situated at one of the towers and acquire the vault keycards. The second mission requires you to travel to two different locations, take the guards out and take the vault keycards. One guard will be drunk on the street while the other will be in a motel room. Just make sure that when you are taking them out, you use a suppressed weapon or kill them using a melee weapon to avoid cops.

Getting the vault keycards from prison is the easiest prep mission. All you need to do is hijack a prisoner bus, head to the prison disguised as a guard and infiltrate one of the towers in the prison. Once you head inside the marked tower, you will come across a guard, just take out the guard silently and search his body for the keycards. After you've acquired the keycards, you can leave the prison the same way you came in, using the bus, and you are done.

You can also go to the prison without hijacking the prison bus, which makes it ten times faster but is also ten times dangerous. Since you won't have a prison guard disguise, as soon as you enter the prison premises, you will get wanted level and the prison guards are alerted. You can still take out the guard at the tower, but you need to be super quick about it since the snipers situated at the prison are extremely strong and will destroy you, sometimes even one-shotting you.

If you have an Oppressor Mark II, it will make doing this method a tad bit easier. However, the snipers are still very strong and can destroy you either way. We do not recommend this method unless you're confident you can do it.

Duggan Shipments

While the 'Duggan Shipments' general prep mission doesn't hold that much importance in both The Big Con and Silent & Sneaky approaches, it holds immense importance in the Aggressive approach.

You may consider it as one of the mandatory prep missions due to how important it is for this approach. In this mission you need to destroy 10 shipments spread throughout the map. They are all far away from one another and it is best to have a friend with you and divide the areas you guys will cover. Going solo is possible but it is really tough to actually pull it off due to the fact that you get only 10 minutes and there are 10 shipments. Having said that, if you manage to destroy all 10 shipments, the guards during the finale will be extremely weak. Their armor will be super low and their aim will be really bad, along with their health. Just a couple of hits and they will go down.

This mission holds significant importance for this Aggressive approach due to the fact that the whole approach is based around you being engaged in combat throughout your finale of the heist. You will be shooting the enemies to go in and then later get out. So it is best to make your life easier by weakening them first.

TIP: Of course we recommend you do this mission with at least one friend. But if you want to do this solo then use either a Buzzard or an Oppressor Mark II. Please note that if you're using an Oppressor Mark II, then you are limited to only 20 rockets. So you need to try and limit your shots. 1 rocket should be used to destroy 1 shipment. Especially when you come across shipments in the helicopter which are protected by an accompanying helicopter. You need to make sure your Oppressor is locking onto the helicopter carrying the shipment. You can identify the shipment helicopter by looking at the mini map, it will be represented by a red cross hair just like the rest of the shipments.

Another important tip regarding the Oppressor Mark II is that its maximum speed on land is 130 km/h, while in air it is 109 km/h. So whenever you are going towards your shipment make sure you spend as much time on land as possible in order to reach the shipments faster. This is very important if you want to complete the mission within the given time limit. Even if you're on the water surface, it will be considered as "on land" and you will get the maximum 130 km/h speed. Make sure you make use of that.

Some people prefer the Hydra as it can cover distances quite fast. The Hydra is pretty good, but only if you have reasonable command of the cannons on the plane. If you cannot use the cannons effectively, it is useless. The homing rockets on the Hydra are not as effective as the ones on Oppressor Mark II or Buzzard. The homing rockets on the Hydra miss the target most of the time.

Patrol Routes (Optional)

Doing the Patrols Routes mission is completely up to you. Doing it will help you during the finale as it will show the position of the guards on your mini map. However, this is most useful in The Big Con approach and Silent & Sneaky approach. In the Aggressive approach you are going in a pure combat situation, eliminating whoever comes in your way and making the positions of the guards irrelevant.

Still, if you want to be on the safe side, you can always carry out this mission. In it, you need to find a specific car and take a photo of the contents of the trunk. The mission location is always different, but the cars are always the same, so you can never mistake the car for any other once you've identified it. There are two possible cars you can get - it can either be a gray colored car or a black colored car. You can either sneak your way to the vehicle or just kill all the guards and then approach it - it is completely up to you. Just make sure when you are going in killing everyone, not to accidentally blow up the target car!

You will see that, for this particular location, there is a black car (circled in green) right next to the gray car (circled in red). So when you arrive at the location, it can be either one of these (and the same goes for other locations as well). You will always get either a gray colored car or a black colored car. The best part is that the mar model will be the exact same in all the locations, so once you've identified it, you'll know exactly what you're looking for during your next run.

Security Pass

You need to acquire a Level 2 Security Pass for the heist so that you can escape easily after looting the vault, since you won't be able to go back out the way you enter from. Going in is easy but going out will be challenging. There are two different types of missions you can be given to get the required security pass. One requires you to go to a pool party and get the card from the croupier. The other requires you to get it off of a dead valet's body while you impersonate a Coroner officer.

Croupier / Party Method

For the first type of mission you will be instructed to go to a pool party. Once you reach the party a suspicion bar, at the bottom right corner of your screen, will become visible. It will gradually increase if you become more noticeable and attract attention, however, you need to blend in and make sure it doesn't rise. You can do different activities such as drinking and dancing to keep the suspicion bar low. Once Lester has identified the target you need to find and search for the keycard on them. They will be passed out and once you search for the keycard you'll discover it's not actually on them. However, it should be laying around somewhere in the area. You need to search for the keycard around the area.

TIP: Your suspicion will still increase slightly, but the best way to keep it low is to go to your interaction menu, set your action to dance, and turn it on permanently. This way you can walk around and search for the card while making sure the suspicion bar is not increasing.

Coroner Method

If you get the coroner mission you will need to go to the church and steal a hearse. Once you do so, the cops will instantly be on you. After losing them head to the coroner's office. You will automatically equip the coroner officer's clothes. Enter the office and proceed to the morgue. Avoid the cops' cones of visions inside the office as much as you can. Once you reach the morgue, search the valet's body and get the keycard. Just ensure that no one is watching you while you do so. After that head back the same way you came in, while avoiding the cops. Leave the area to successfully complete the prep mission.

Approach Specific Preps

You need to do all the approach specific prep missions along with the mandatory prep missions of course. You can skip one mission, however, which is the reinforced armor mission. If you're already an experienced player, then there's no need to waste your energy on this mission as you will already have maximum health and armor at this point. But if you are a low level player then by all means go for it.

Let's take a lot at the rest of the approach specific missions that you will need to carry out for this.

Thermal Charges

Getting thermal charges is pretty simple and straightforward. All you need to do is go to a specific location as directed by the game, take out the agents and get the thermal charges from the warehouse. Note that there will be quite a lot of agents so you need to be prepared with snacks and armor in order to easily fight them all. Once you take out the agents you can look for the Thermal Charges. They will be in a wooden crate. Grab the thermal charges and leave the warehouse delivering the charges back to the Arcade.

The mission is fairly simple and easy, however we recommend you have another friend with you as doing it solo will require you to return back to the warehouse to carry the second crate of thermal charges back to the Arcade.

Vault Explosives

This prep mission is the toughest to carry out if you're doing it solo so we recommend getting a friend. You can totally do it solo, but it will take a very long time to be completed. This mission requires you to go to Alamo Sea and search the plane wreckage for vault explosives. However, the area will be crawling with Merryweather soldiers. There will be several at the little pier of Alamo Sea where you can also find Scuba Diving Gear to put on, in order to search the wreckage, and there will be two helicopters along with some boats at the wreckage site as well. Getting the scuba gear is not mandatory though.

Before starting this mission get some rebreathers from ammu-nation and put them on prior to starting the mission or else you won't be able to put them on. Head over to the site and take out all the guards, then dive in to search for the vault explosives. Once you get the explosives you will need to head back to the Arcade to deliver it. Now, if you're doing it solo then you will need to come back and get the second crate as well. Every time you come back, you will see the Merryweather helicopters respawning over the wreckage site and you will need to take them out every time. Also, when you grab the crate and start moving towards the Arcade, the helicopters will spawn again and chase you down. So you need to make sure you have a getaway vehicle or a boat that you can take to the site and use to easily head back to the shore.

TIP: Here's an "unpopular" tip from us if you're doing this solo. If you have an Oppressor Mark II, then head over to the location, take out all the guards and then dive into the water to locate the vault explosive crates. Once you get the crate, you will unfortunately have to swim back to the shore since jumping off of your Oppressor will destroy it as soon as it goes in the water. One you're on the surface after getting the crate, the helicopters will spawn again and come shooting at you. Do not worry about it and let them kill you, but make sure you are swimming above the surface and not underwater when you die. Now your crate will be on top of the water surface instead of deep underwater.

When you spawn back, you will spawn at the shore. Call Mors Mutual insurance and request your Oppressor Mark II again. Once it arrives. Hope on it and collect the crate. You will be able to collect it while you're on your Oppressor. Then simply head back to the Arcade and deliver the first crate. Repeat for the second crate and you are done with it.

See all that effort? Why not save yourself some time and energy and just do this mission with a friend. It'll be much better!

Boring Machine

This is an optional approach-specific prep mission but it will make your finale much easier and faster. If you get this boring machine and also take a picture of the Sewer Grates in the sewer tunnel near the Diamond Casino then you will be able to access the casino vault very easily. You can just put explosives on the wall which leads to the vault security lobby area and then head directly into the mantrap leading to the vault.

You will need to go to one of the construction sites and steal the boring machine. There will be some resistance from the construction workers and guards there but you can easily take them out and get into the truck which is carrying the machine. You will have cops on you, but a fortunate thing about this heist prep mission is that you can easily lose the cops by calling Lester from your phone (unlike for other missions in GTA Online). After you've lost the cops just head to the sewer, leave the tunnel boring machine there, and you should be done with this prep mission.

You can see the final prep board below showing the missions that can be skipped, missions that are needed to be done and a mission which is not necessary to do, but can make your heist finale easier.

Heist Finale

Final Prep Board

On the final prep board you can choose the entry point, exit point, your buyer, clean vehicle and gunman decoy.

Entrance: Choose SEWERS as your entrance.

Exit: You can choose either WASTE DISPOSAL or STAFF LOBBY. The later is our recommended exit strategy.

Buyer: Your choice but we recommend you choose a HIGH LEVEL buyer for maximum profit.

Clean Vehicle: Not necessary

Gunman Decoy: Not necessary

Heist Finale

You can check our full video guide here too.

As always, head towards the casino but not the side doors, the roof or the main entrance. You will head straight for the sewer tunnels. Once you reach the tunnel there will be a door already set up for you, which will lead you directly to the wall to the vault security lobby. Head through the door and at the end there will be a mark on the wall where you are supposed to plant your explosives. Plant the explosives and a cut scene will appear in which the wall is blasted open, followed by you and your partner going through it and the wall being shut closed behind you due to debris.

Once you're inside kill all of the guards. Since you have already done the Duggan Shipment prep mission, this will be a walk in the park for you. Just take cover, take your time and do not rush anything. Take them all out one by one and then head for the mantrap entrance. Time the keycard swiping with your friend, open up the mantrap and head to the vault.

Once you reach the vault, plant explosives on the vault. Once that is done a new contact will be added in your phone called 'Detonate Bomb', call that and the explosives will go off, leaving the vault entrance wide open for you. Once you get inside quickly loot all of it. Since you have thermal charges, you can also open up locked doors using the charges, without having to hack them and saving you some time. After you've looted the vault, leave it when the timer hits the 30-40 seconds mark just to be safe. When a minimum of 25 seconds are left just leave whatever you're looting and head for the exit.

Once you're outside again, you and your friend will have to swipe the keycards simultaneously to open the entrance to the mantrap. Do so and head back the same way you came from. Once you reach the vault security lobby again, more guards would have spawned there by now. Take them all out while taking cover behind walls and doors. After taking them all out head for the elevator outside. You won't be able to leave the same way you entered the area (via the sewer tunnels) because that entrance is now blocked by debris. Head for the elevator and you will be taken to the staff lobby floor.

While heading to the staff lobby floor, make sure you pre-aim while still inside the elevator and before leaving since sometimes there are guards right outside and holding a shotgun which can instant kill you. But, that shouldn't be the case if you've already completed the Duggan Shipment prep mission as that would have weakened all the guards. As soon as you are outside the elevator take an immediate right and then another right, heading towards two doors. Take cover and take some guards out before heading through those two doors. Once you go through the doors take a left and another left where you will come across a long hallway that leads to the staff lobby. There will be a bunch of guards ambushing you along the way. Keep taking them out while carefully pushing forward until you reach the end.

Once you reach the end of the hallway take cover by the double door. This double door will take you directly out into the staff lobby, from where you can finally exit. Take cover here and take out guards in the lobby. Once you think it is safe for you to leave, head straight for the staff lobby exit which is through the metal detectors to your right as soon as you pass the double doors.

As soon as you exit through the staff lobby head straight to the racetrack and run on the right side of the track. Keep running until you reach the end, where the track will descend down towards your right. Go down and then hop over the fence, out on the street and get a pedestrian car. After getting the pedestrian car head straight towards the sewer tunnels and stay in the middle of the tunnels until you've lost the cops. These are the same tunnels where you entered the casino vault section from. After the cops are gone, continue through the tunnel and come out of the other end of the tunnel.

Once you're outside the tunnels make sure you do not go near the casino once again. Take a route to the buyer that is different to one which would cause you to go through the highway next to the casino. So you need to make your own way-point towards the buyer and detour around the highway. Also, for those who don't know exactly where the sewer tunnels entrance is, refer to the picture below.

Once you've successfully delivered to the buyer, your heist ends there.

Frequently Asked Questions