Home › Field Guide
The Door Breaching Field Guide
Every door, every tool and every rating in the game, with the math behind them. Read this if you want a "Surgical" rating. Skip it if you'd rather hit a bank vault with a rubber chicken and find out for yourself.
How damage works
Every door has HP (how much damage it takes to get through) and armor, rated 0 to 9. Every tool has damage and penetration (PEN), also rated 0 to 10.
If a tool's PEN is equal to or higher than the door's armor, the tool does full damage. For every point it falls short, its damage is cut in half, down to a floor of 1%. A Halligan Bar (PEN 3) on a Steel Security Door (armor 4) does half damage. A Battering Ram (PEN 4) on a Bank Vault (armor 7) does one eighth.
On top of that, every hit varies by up to 20% either way, and 1 hit in 10 is a critical hit that does double damage. That's why the hit estimate in the game is an estimate.
The doors
| Door | HP | Armor | Answers a knock? |
|---|---|---|---|
| Paper Shoji Screen | 5 | 0 | Yes |
| Screen Door | 12 | 0 | Yes |
| Hollow-Core Bedroom Door | 40 | 1 | Yes |
| Solid Oak Front Door | 150 | 2 | Yes |
| Steel Security Door | 500 | 4 | Yes |
| Bank Vault Door | 3,000 | 7 | Never |
| Bunker Blast Door | 12,000 | 9 | Never |
Paper Shoji Screen
Five HP and no armor. Everything works, including the pool noodle, which gets through in about three swats. This is the door to use when you want to see an overkill tool at its most ridiculous: an orbital laser on a shoji screen is roughly a hundred thousand times more damage than needed.
Screen Door
Twelve HP and no armor. A single Shoulder Barge usually does it. A Stale Baguette takes about four hits, which feels right. The screen door is also a good place to practice the Polite Knock, since grandma is usually home.
Hollow-Core Bedroom Door
Mostly cardboard, with one point of armor. Two Boot Kicks are enough. The rubber chicken has PEN 0, so it does half damage here and needs around 75 squeaks. Behind it there's usually a teenager with opinions about knocking.
Solid Oak Front Door
The classic. 150 HP and armor 2. The Battering Ram is the textbook choice: three hits, no wasted damage and a "Surgical" rating. A Halligan Bar takes about five. Kicking works, but it takes around seven, and it looks less heroic each time.
Steel Security Door
This is where silly tools stop working. Armor 4 means anything with PEN 1 or less does an eighth of its damage or worse. The Battering Ram still does full damage and gets through in about seven hits. The Chainsaw (PEN 4) works if you hold it down for around 80 cuts. The Thermal Lance burns through in roughly two dozen.
Bank Vault Door
3,000 HP, armor 7, and nobody will ever answer the knock. Only the Thermal Lance and the overkill tier do full damage. A Breaching Charge takes about four blasts. A Wrecking Ball takes two. The Battering Ram does one eighth damage, so expect more than 300 hits. The rubber chicken does 1%: about 300,000 squeaks. The game will let you try.
Bunker Blast Door
12,000 HP and armor 9, the toughest door in the game. Only the Tank Shell, the Orbital Laser and the Small Asteroid do full damage. Here's the twist: a single Tank Shell does about 15,000 damage, which is barely more than the door's HP. That makes the tank the one "Surgical" overkill weapon in the game. The Thermal Lance does half damage and needs close to a thousand cuts, which can earn the rare "Determined Beyond Reason" rating.
The tools
| Tool | Tier | Damage | PEN | Notes |
|---|---|---|---|---|
| Polite Knock | Silly | 0 | 0 | 12% chance someone opens up |
| Rubber Chicken | Silly | 1 | 0 | Fast and squeaky |
| Pool Noodle | Silly | 2 | 0 | Floppy |
| Stale Baguette | Silly | 3 | 1 | Drops crumbs |
| Shoulder Barge | Standard | 14 | 1 | Hurts in real life |
| Boot Kick | Standard | 20 | 2 | |
| Halligan Bar | Standard | 28 | 3 | |
| Battering Ram | Standard | 70 | 4 | Slow, heavy |
| Chainsaw | Standard | 6 | 4 | Hold to saw |
| Thermal Lance | Standard | 22 | 8 | Hold to cut |
| Breaching Charge | Overkill | 900 | 7 | Short fuse |
| Wrecking Ball | Overkill | 2,500 | 8 | |
| Tank Shell | Overkill | 15,000 | 9 | |
| Orbital Laser | Overkill | 500,000 | 10 | Takes a second to arrive |
| Small Asteroid | Overkill | 1 billion | 10 | Ask the dinosaurs |
The Polite Knock
The knock does zero damage, but each knock has a 12% chance that someone opens the door, so it takes about eight knocks on average. Getting in this way earns the "Social Engineer" rating: no damage, no collateral, frame intact. It never works on the vault or the blast door, because nobody lives there.
Hold-to-use tools
The Chainsaw and the Thermal Lance fire many small hits per second while you hold the mouse button, your finger or the Space bar down. They're the best choice when the big tools can't penetrate and the overkill tier feels like cheating.
The overkill tier
Overkill tools take a moment to arrive. The charge has to be planted, the ball has to swing and the asteroid has to fall from orbit. Each one hits hard enough to flatten almost anything, and that's the point.
Ratings
When the door goes down, the game rates your breach on two numbers: how many hits it took, and your overkill ratio, meaning total damage dealt divided by the door's HP. A ratio of 1× is perfect. A ratio of 1,000× means you brought far too much.
- Social Engineer: someone opened the door for you.
- Surgical: three hits or fewer, and less than double the damage needed.
- Professional: clean and efficient, just not quite surgical.
- Enthusiastic: 2× to 10× overkill.
- Persistent: 100+ hits with the wrong tool.
- Overkill: 10× to 100× more damage than needed.
- Catastrophic Overkill: 100× or more.
- Extinction-Level Overkill: a million times more. Small Asteroid on anything soft.
- Determined Beyond Reason: 1,000 hits or more. The door respects you.
There are 105 door-and-tool combinations. The game keeps count of the ones you've finished, in your browser only. Ready? Pick a door →