Without a doubt, Fallout Shelter has become a mobile gaming darling among Fallout junkies and fair-weather gamers alike. It’s insanely simple to play, challenging and addicting.

For those that don’t know, Bethesda last week released a ton of info about the upcoming Fallout 4 (slated for Nov. 10, 2015) at E3. As a side note, they announced the release of Fallout Shelter, a mobile app similar in style to Sim City, but taking place after the nuclear war of 2077 (much like the rest of the Fallout series). Fallout Shelter launched the day it was announced, and soon became the top game in the Apple App Store, beating out the massively popular Candy Crush.

The game is easy enough to play. A handful of people want access to your underground bunker (also known as a vault) to escape the radiation. You invite them in and let them tend to the power generators, restaurants and water treatment plants. As they give birth to new vault dwellers (or as more people come knocking on your door), you can build more utility rooms and training centers to raise dweller stats and gain money (bottle caps in this case). You can also send vault dwellers into the wasteland to fight for additional caps, weapons and clothing.

Without a doubt, you will probably make a few false moves on your first pass at the game and scrap it and start again. To save yourself some time (and caps) here are nine Fallout Shelter advanced tips for kicking ass in the wasteland from the get-go.

1. Don’t go on a building spree if you don’t have enough bodies to fill the rooms. Just because you built a giant water treatment facility, doesn’t mean it will produce more water faster. You need to have bodies to fill it. Only then will you increase the speed of production. Your best bet is to build one room and fill it with two workers. Don’t add a second room until you have another worker with the appropriate skills (also known as perks) to run the room efficiently. Instead, use your caps to upgrade the room.

2. Demolish rooms that aren’t being used. Unused rooms attract radroaches, eat up power and are a waste of space. If you aren’t using a room (due to a recent massacre or radroach infestation), knock down the room and collect some caps that you can use towards a room that you do need. Obviously, you shouldn’t knock down a maxed out nuclear reactor, but don’t think twice about knocking down that diner you were forced to build right next to the water treatment plant during the tutorial.

3. Create a vault dweller boot camp. As the number of denizens in your vault increase and your workers are producing the right amount of utilities, establish a process to cycle vault dwellers through training centers. Move dwellers from utility rooms to training rooms and then back again as they increase their skills for that room.

4. Balance lame skills with needed skills. For a good chunk of the game, the skills you rely on the most are strength (to run the power plants), perception (to run the water treatment plant) and agility (to run the restaurant). Intelligence is useful for making meds and anti-radiation treatments, but you don’t need that many smart people. The rest of the skills — charisma, endurance, luck — are pretty much useless until you are well established. The bad news is that you almost always end up with new dwellers with none of the skills you need. Once you save up enough for a training camp, start dumping new residents with lame skills into a training room that builds the perks that you want. Don’t just shuffle a weak dweller into a room to fill a space.

5. Strengthen your defenses. Build a power generator or nuclear plant in the room next to the vault door, fill it with your strongest vault dwellers and arm them to the teeth. That’s the room raiders go to first when they break into your vault, so you might as well take care of them before they do damage to your weaker dwellers.

6. Breed stronger babies. Bethesda stated that you can’t “game the system” by breeding super babies by mating dwellers with high skill levels, but that’s not necessarily true. If you have two dwellers that both have high strength (or whatever skill you need), their baby will lean towards that skill. Need more people for your water treatment plant? Mate two dwellers with higher perception.

7. Create a few super soldiers. Once you have all your training rooms in place and you are upgrading them as needed, consider taking two or four dwellers (preferably pairs of men and women) and max out their perks. These are the warriors that you can send out into the wasteland overnight and know that they won’t be dead in the morning. I like to max out one perk and then send them out into the wasteland, then bring them back when the other super soldier maxes out a perk and swap them out.

8. Put a weapon in every room. Radroaches are evil and if they infest a room with weak dwellers, your people will die quickly. Make sure you arm half the people in every room and pull the unarmed dwellers out of that room the moment the roaches attack. Even better, swap them out with the armed people from the room next door. If you wait too long, the roaches will move onto another room. That’s not a good thing.

9. Don’t buy lunch boxes. After playing for a few hours and struggling to gain good dwellers, you might get the urge to drop a few bucks on a lunchbox (often filled with goodies, such as strong dwellers and big guns). Don’t do it. Not only does it decrease the challenge and fun, but you can’t use a purchased lunchbox more than once. If you start a new game, that lunchbox you dropped $2 on is gone.

I hope I helped make your stay in Vault 138 (or whatever yours is numbered) a little bit more pleasant. Feel free to leave additional tips in the comments section below. I might even update the article if I find something else interesting. And don’t forget — War never changes.