Your wallet is not the wall
In Dig 2, gold accumulates far faster than it can be spent. The Pressure Bomb line — the most important one in the game — costs a grand total of 1,100 gold to take from the starting tier to the top.
And yet you cannot buy it early. Because the real gate is level:
| Tier | Cost | Level required |
|---|---|---|
| Osmotic Ticker | — | 1 |
| Scholander Hydrostatic | 100 | 1 |
| Acid Bomb | 300 | 1 |
| Bomp Bah Bomb | 1,000 | 14 |
You can have the 1,000 gold sitting in your pocket at level 8 and the shop will still refuse you. The same level-14 wall stands in front of the final Water Tank (Nautilus II) and the final Lamp (Sol Invictus).
So the practical rule is: do not hoard. Spend on the cheap early tiers that are actually available, and know that the last rank of each line opens at the same moment.
The one mod you must buy first
Sky Assailant, the Pressure Bomb’s level-4 mod, lets you shoot bombs in mid-air.
That is not a damage upgrade. It is a key. A large share of Dig 2’s secrets sit behind sand blocks in the ceiling that you cannot reach by jumping and cannot hit by throwing. Sky Assailant is the only thing that opens them.
Getting it costs:
- A level 4 Pressure Bomb — which requires level 14.
- 1,000 gold for the tier itself (1,400 total if you have bought nothing else in the line).
- 3 upgrade cogs to unlock the mod.
Do this before you start serious hunting. Otherwise you will find cracked blocks you cannot open, and have to leave and come back.
The Pickaxe
| Tier | Level | Cost | Mod | Cogs | Effect |
|---|---|---|---|---|---|
| Rusty Pickaxe | 1 | — | — | — | — |
| Iron Pickaxe | 1 | 25 | Hunter’s Edge | 1 | +5 XP per enemy killed with the pickaxe |
| Bardur-Grip Pickaxe | 1 | 80 | Resource Roughhouse | 2 | Extra damage to resource tiles |
| Pickaxe Chu | 1 | 200 | Bounty Hunter | 3 | Cash prize for enemies killed with the pickaxe |
| Alloy Steel Pickaxe | 6 | 350 | Total Recoil | 1 | Pushes enemies back further |
| Tungesten Pickaxe | 6 | 500 | Healer | 3 | Chance of an extra health orb from pickaxe kills |
| Barren North Pickaxe | 6 | 700 | Return to Sender | 2 | Hit projectiles mid-air to reverse them |
| Templar Bickaxe | 10 | 1,000 | Mid-Tile Express | 3 | Faster swing |
Unique: 21 Artifacts → Sharpened Edge (4 cogs) — extra damage to enemies. · Combuster’s Station Cave → Ignition Axe — adds fire and range, and it is what opens Demon’s Crib.
Two of these are secretly money-making mods rather than combat mods. Hunter’s Edge is an XP engine that is available at level 1 for 25 gold, and Bounty Hunter pays you for doing what you were already doing. If you take one early mod, take Hunter’s Edge.
The Bag
| Tier | Level | Cost | Mod | Cogs | Effect |
|---|---|---|---|---|---|
| Miner’s Pack | 1 | — | — | — | — |
| Shrewhide Pack | 1 | 8 | Reaper’s Discount | 2 | Lose fewer resources when you die |
| Bag of Holding | 1 | 30 | Cash on Disposal | 1 | Discarding a resource pays you a share |
| Trojan Sack | 1 | 75 | Dual Depot | 2 | Store two gems per slot |
| I-Can’t-Believe-It’s-Just-A-Bag | 1 | 125 | Portal of Pardon | 3 | Instant return to El Machino with no resource loss |
| Germlin Carry | 6 | 200 | Double Rainbow | 4 | Chance of two resources from one tile |
| Elven Tote | 6 | 300 | Magnetic Separator | 2 | Pulls exposed resources toward you |
| One Bag to Hold Them All | 6 | 450 | Hobo King | 3 | Instant cash from low-value resources — does nothing for resources above $7 |
| Mammoth Pack | 10 | 800 | Re-Circle of Life | 1 | Discarding resources restores health; gems restore more |
| Bag-Avad Get’a | 10 | 1,500 | Yuppie Ki-Yay | — | 30% more cash when selling |
Unique: 10 Artifacts → Pocket of Freyr (5 cogs) — one extra ore chunk per regular slot.
The bag line is where the money is. Yuppie Ki-Yay is a flat 30% on every sale and costs no cogs at all, which makes it the single best economic mod in the game. Hobo King is the trap of the line — it is worth 3 cogs but explicitly does nothing for anything worth more than $7, so it pays out only on your junk.
Note also that Portal of Pardon is disabled in caves and whenever you are in danger, with the icon showing you when it will not work.
The Lamp
| Tier | Level | Cost | Mod | Cogs | Effect |
|---|---|---|---|---|---|
| Broken Lamp | 1 | — | — | — | — |
| Rock-Bottom Lamp | 1 | 6 | — | — | — |
| Miner’s Brite | 1 | 20 | Larger Than Light | 1 | Bigger light radius |
| Modified Carbide Lamp | 1 | 50 | Flames of Kubera | 1 | Pickups emit light, so they are easier to find |
| Lodestar | 1 | 100 | Gordon Reflexes | 2 | Chance of auto-dodging falling rocks |
| Lantern | 6 | 150 | Summoner | 2 | Chance of an extra light orb from enemies |
| Pharos Light | 6 | 250 | Spotless Mind | 3 | Light never drops below 50% |
| Sol Invictus | 14 | 500 | Eye for Weakness | 3 | See the weak parts of walls when you shine on them |
Eye for Weakness is the sleeper pick of the whole game. Lights up the weak parts of walls — which is precisely the information you need when you are hunting for a hidden block and do not know which one is breakable.
The Armor
| Tier | Level | Cost | Mod | Cogs | Effect |
|---|---|---|---|---|---|
| Plate Armor | 1 | — | — | — | — |
| Sturdy Armor | 3 | 25 | Cougar Paws | 2 | Reduces fall damage |
| Hard Armor | 3 | 75 | Karma Plates | 1 | Damages anything that injures you by touch |
| Tempered Armor | 3 | 150 | Vidar Boots | 3 | Brief acid and lava resistance |
| Famed Armor | 6 | 250 | Aramid Armor | 3 | Deflects the first projectile; 30s recharge |
| Doom Armor | 6 | 400 | — | — | — |
| Full Moon Armor | 6 | 600 | — | — | — |
| Phoenix Armor | 10 | 1,200 | True Survivor | 5 | First lethal damage instead restores full HP; resets in town |
Unique: The Sun Armory Cave → Ultra Composite Armor — reduces damage taken. · 6 Artifacts → Core Diversity (1 cog) — small chance of 3 Rainbow Orbs per enemy defeated.
True Survivor is the best defensive mod in the game and it costs 5 cogs, the joint-highest in the game. It is a full-HP revival that recharges for free every time you visit town — which, if you are teleporting back to sell regularly, is constantly.
Note that Vidar Boots is worth building toward before you enter Vectron: the lava and acid there will otherwise end runs.
The Water Tank
| Tier | Level | Cost | Mod | Cogs | Effect |
|---|---|---|---|---|---|
| Plain Jar | 1 | — | — | — | — |
| Melville Regulator | 1 | 75 | Pump Up The Jam | 1 | Absorbs water faster from pools |
| The Notorious W.E.T. | 1 | 300 | — | — | — |
| The Cisterns of Mercy | 6 | 650 | Storm Chaser | 1 | Turns Light Orbs into Water Orbs |
| Nautilus II | 14 | 1,400 | Moisture Vaporator | 5 | Constantly replenishes water from moisture |
Unique: 28 Artifacts → Aquatic Regenesis (5 cogs) — regenerates life while standing in water.
Water is the fuel for your Pressure Bomb, your Jetpack and your Jackhammer, so the tank is a combat stat disguised as a utility. Moisture Vaporator at 5 cogs removes refilling from the game entirely, and it is the reason the level-14 Water Tank is worth the wait.
The Pressure Bomb
| Tier | Level | Cost | Mod | Cogs | Effect |
|---|---|---|---|---|---|
| Osmotic Ticker | 1 | — | Molotov Vaccination | 1 | Bombs stop hurting you |
| Scholander Hydrostatic | 1 | 100 | Wet Wet Wet Bomb | 3 | Extra water orb from tiles destroyed by bombs |
| Acid Bomb | 1 | 300 | Buster Shells | 1 | Shatters harder rocks |
| Bomp Bah Bomb | 14 | 1,000 | Sky Assailant | 3 | Shoot bombs mid-air |
Unique: Chamber of Secrets Cave → Grenade Launcher — hold the button to lob a grenade in an arc. · 500 gold from Clifford Heisenberg at the top of El Machino → Threeforce Grenade (3 cogs) — charged shots fire three.
Every tier here has a purpose, and they are not competing:
- Molotov Vaccination first, because the alternative is blowing yourself up in a corridor.
- Buster Shells for the harder rock types.
- Sky Assailant for everything hidden.
The four unique mods you cannot buy
| Mod | Source |
|---|---|
| Ignition Axe | Combuster’s Station Cave |
| Ultra Composite Armor | The Sun Armory Cave |
| Grenade Launcher | Chamber of Secrets Cave |
| Threeforce Grenade | 500 gold from Clifford Heisenberg, at the top of El Machino |
And four more behind the artifact collection:
| Mod | Artifacts needed | Cogs |
|---|---|---|
| Core Diversity | 6 | 1 |
| Pocket of Freyr | 10 | 5 |
| Sharpened Edge | 21 | 4 |
| Aquatic Regenesis | 28 | 5 |
These are the last things you will unlock in the game, and the 28-artifact one is a genuine completionist target rather than a build piece.
Cogs are free to move
Cogs come from hidden alcoves and Challenge Caves, and you slot them at any workbench in El Machino. They can be removed and reallocated at any time, with no penalty.
There is therefore no such thing as a wrong build. Slot Hunter’s Edge and the money mods when you are farming, then pull them out for True Survivor before a boss.