Save the Earth - The Incremental created by Kawloran and Zaloran.
Images used for educational purposes only.
This article is, at the moment, a sneak preview of sorts of the Save the Earth walkthrough that is to come. The game takes a while to 'complete' - as is pretty damned common with idle browser games - and I'm still compiling information on various facets of the game, most notably the Advanced Research options. Once I have a bit more meat to work with I'll polish this document up, add descriptive text for newcomers, and continue to edit in new information as I get it.

You might also want to play the game. It's pretty rad. Support your indie game developers, y'all.

A few things to note about this walkthrough:

- The initial price of the units listed below is only applicable to the first unit you purchase. Each unit after that gets progressively more expensive, to the point that a mere Soldier can cost trillions of dollars.
- The RPS listed beside the units is the base RPS. As you purchase Research upgrades the RPS will rise drastically.
- In order to unlock a new unit you must purchase at least five of the previous unit in the tier list.
- Basic Research upgrades are unlocked whenever you have enough money / RP available. Advanced Research upgrades, on the other hand, have certain prerequisites (create enough of a certain troop, pass a certain amount of Global money collected, things like that) that must be fulfilled before they can be purchased. Hence the reason I haven't listed any yet, as the game doesn't tell you what the prerequisites are. Sigh. Oh well.
- Ranks (available for purchase on the Attainments menu) are the only things beside passive bonuses (listed near the bottom of the Attainments menu) which carry over when you Reset your game. Everything else you've accumulated disappears upon Resetting. Make sure you purchase all four sections of a Rank before Resetting, or you'll pretty much have wasted your time with your previous run.

A shot of the rambling army that will eventually grow in Save the Earth - The Incremental.
A shot of the rambling army that will eventually grow in Save the Earth - The Incremental.
Units
  • Soldier - $15 - 0.3 RPS
  • Bazooka - $100, 5 Soldiers - 0.5 RPS
  • Mortar - $500, 5 Bazookas - 4 RPS
  • Jeep - $3,000, 5 Bazookas - 10 RPS
  • A.A. Jeep - $10,000, 5 Jeeps - 40 RPS
  • Tank - $40,000, 5 A.A. Jeeps - 100 RPS
  • B.F.A.A. - $200,000, 5 Tanks - 400 FPS
  • M. Launcher - $1.5 million, 5 B.F.A.A.s - 6,666 FPS
  • Aircraft - $125 million, 5 M. Launchers - 98,765 FPS
  • Chopper - $3 billion, 5 Aircraft - 1,503,000 FPS

A shot of the Basic Research options in Save the Earth - The Incremental
A shot of the Basic Research options in Save the Earth - The Incremental
Basic Research

Experience
  • The Final Countdown - $20,000 - Receive timed experience based on your current level
  • Area 51 - $250,000 - Doubles base XP
  • Click ‘em All - $100,000, 1 RP - Base click provides 10% of total RPS; increment per click is doubled
  • Clicking Bad - $500,000, 1 RP - Triples base XP
  • Reaction Rates - $1 million, 1 RP - Triples base XP; increment per click is doubled
  • Absurd Speed - $20 million, 1 RP - XP per second increased by your level multiplied by 25; increment per click is doubled
Soldier
  • Protein X Serum - $100, 1 RP - Doubles the Soldier’s RPS
  • Universal Soldiers - $400, 1 RP - Doubles the Soldier’s RPS
  • The Incredible Boost - $1,000, 1 RP - Doubles the Soldier’s RPS
  • Earth’s Defenders - $5,000, 1 RP - Grants 0.1 RPS bonus to each Soldier for every 10 Soldiers purchased - bonus increases sequentially 
  • Supply Lines - $5,000, 1 RP - Grants 0.1 RPS bonus to each Bazooka for every 10 Soldiers purchased - bonus increases sequentially 
  • Lazy Sunday - $50,000, 1 RP - Eliminates the need for Soldiers to purchase additional Bazookas
Bazooka
  • Prototype XH-503 - $1,000, 1 RP - Doubles the Bazooka’s RPS
  • Prototype XH-Turbo - $6,000, 1 RP - Doubles the Bazooka’s RPS
  • Prototype XH-Ultra - $20,000, 1 RP - Doubles the Bazooka’s RPS
  • Assault Platoon - $50,000, 1 RP - Grants 0.5 RPS bonus to each Bazooka for every 10 Bazookas purchased - bonus increases sequentially 
  • Eyes on the Sky- $50,000, 1 RP - Grants 0.5 RPS bonus to each Mortar for every 10 Bazookas purchased - bonus increases sequentially 
  • The Old Barracks - $200,000, 1 RP - Eliminates the need for Bazookas to purchase additional Mortars
Mortar
  • Longer Range - $20,000, 1 RP - Doubles the Mortar’s RPS
  • Awesome Range - $45,000, 1 RP - Doubles the Mortar’s RPS
  • Insane Range - $75,000, 1 RP - Doubles the Mortar’s RPS
  • Share the Supplies - $125,000, 1 RP - Grants 2 RPS bonus to each Mortar for every 10 Mortars purchased - bonus increases sequentially 
  • Mobile Mortars - $125,000, 1 RP - Grants 2 RPS bonus to each Jeep for every 10 Mortars purchased - bonus increases sequentially 
  • Mortal Kombat - $500,000, 1 RP - Eliminates the need for Mortars to purchase additional Jeeps
Jeep
  • Death on Wheels - $125,000, 1 RP - Doubles the Jeep’s RPS
  • Fine Machinery - $300,000, 1 RP - Doubles the Jeep’s RPS
  • Reinforced Hull - $750,000, 1 RP - Doubles the Jeep’s RPS 
  • Moral Boost - $1.5 million, 1 RP - Grants 8 RPS bonus to each Jeep for every 10 Jeeps purchased - bonus increases sequentially 
  • Mobile Mortars - $1.5 million, 1 RP - Grants 8 RPS bonus to each A.A. Jeep for every 10 Jeeps purchased - bonus increases sequentially 
  • Pit Stop - $4 million, 1 RP - Eliminates the need for Jeeps to purchase additional A.A. Jeeps
A.A. Jeep
  • Red Skies - $750,000, 1 RP - Doubles the A.A. Jeep’s RPS
  • Six Pack - $2 million, 1 RP - Doubles the A.A. Jeep’s RPS
  • Full Metal - $4 million, 1 RP - Doubles the A.A. Jeep’s RPS
  • Fire in the Hole - $7.5 million, 1 RP - Grants 30 RPS bonus to each A.A. Jeep for every 10 A.A. Jeeps purchased - bonus increases sequentially 
  • Advanced Wars 2 - $7.5 million, 1 RP - Grants 30 RPS bonus to each Tanks for every 10 A.A. Jeeps purchased - bonus increases sequentially 
  • Garage Inc - $20 million, 1 RP - Eliminates the need for A.A. Jeeps to purchase additional Tanks
Tank
  • Heavy Deployment - $4 million, 1 RP - Doubles the Tank’s RPS
  • Heavy Fire - $10 million, 1 RP - Doubles the Tank’s RPS
  • Trigun - $15 million, 1 RP - Doubles the Tank’s RPS
  • Reinforce! - $30 million, 1 RP - Grants 80 RPS bonus to each Tank for every 10 Tanks purchased - bonus increases sequentially 
  • Heavy Metal - $30 million, 1 RP - Grants 80 RPS bonus to each B.F.A.A. for every 10 Tanks purchased - bonus increases sequentially 
  • Complete Patch - $75 million, 1 RP - Eliminates the need for Tanks to purchase additional B.F.A.A.s
B.F.A.A.
  • Aerial Panic - $15 million, 1 RP - Doubles the B.F.A.A.’s FPS
  • Locked ’n’ Loaded - $30 million, 1 RP - Doubles the B.F.A.A.’s FPS
  • Stinger Battery - $50 million, 1 RP - Doubles the B.F.A.A.’s FPS
  • Missile Barrage - $80 million, 1 RP - Grants 200 RPS bonus to each B.F.A.A. for every 10 B.F.A.A.s purchased - bonus increases sequentially 
  • Nightwatch - $80 millions, 1 RP - Grants 200 RPS bonus to each M. Launcher for every 10 B.F.A.A.s purchased - bonus increases sequentially 
  • To the Warehouse - $250 million, 1 RP - Eliminates the need for B.F.A.A.s to purchase additional M. Launchers
M. Launcher
  • Tetsu Bo-Hiya - $150 million, 1 RP - Doubles the M. Launcher’s RPS
  • Suchiru Bo-Hiya - $300 million, 1 RP - Doubles the M. Launcher’s RPS
  • Gorudo Bo-Hiya - $750 million, 1 RP - Doubles the M. Launcher’s RPS
  • Hiya Taihou - $1.5 billion, 1 RP - Grants 2,500 RPS bonus to each M. Launcher for every 5 M. Launchers purchased - bonus increases sequentially 
  • Namari no Sora - $1.5 billion, 1 RP - Grants 2,500 RPS bonus to each Aircraft for every 5 M. Launchers purchased - bonus increases sequentially 
  • Nokori - $5 billion, 1 RP - Eliminates the need for M. Launchers to purchase additional Aircraft
Aircraft
  • Rogue Squadron - $750 million, 1 RP - Doubles the Aircraft’s RPS
  • Renegade Squadron - $1.5 billion, 1 RP - Doubles the Aircraft’s RPS
  • Red Squadron - $4 billion, 1 RP - Doubles the Aircraft’s RPS
  • It’s a Tarp! - $8 billion, 1 RP - Grants 50,000 RPS bonus to each Aircraft for every 5 Aircraft purchased - bonus increases sequentially 
  • Air Refueling Squadron - $8 billion, 1 RP - Grants 50,000 RPS bonus to each Chopper for every 5 Aircraft purchased - bonus increases sequentially
  • Hangar - $25 billion, 1 RP - Eliminates the need for Aircraft to purchase additional Choppers
Chopper
  • Firebringer - $10 billion, 1 RP - Doubles the Chopper’s RPS
  • Weepblade - $20 billion, 1 RP - Doubles the Chopper’s RPS
  • Apocalypse Now - $50 billion, 1 RP - Doubles the Chopper’s RPS
  • Blue Thunder - $100 billion, 1 RP - Grants 250,000 RPS bonus to each Chopper for every 5 Choppers purchased - bonus increases sequentially
  • Rescue Mission - $100 billion, 1 RP - Grants 3,000 RPS bonus to each Soldier for every 5 Choppers purchased - bonus increases sequentially
  • Spoils of War - $10 billion, 1 RP - Bonus increment is 20 times more efficient
Advanced Research
  • Officer’s Academy - $10 billion, 2 RP - Triples Soldier RPS
  • Flammable Ammo - $15 billion, 2 RP - Triples Bazooka RPS
  • Mortar and Pestle - $20 billion, 2 RP - Triples Mortar RPS
  • THX1138 Engine - $25 billion, 2 RP - Triples Jeep RPS
  • Handyman - $30 billion, 2 RP - Triples A.A. Jeep RPS
  • Quadrigun - $35 billion, 2 RP - Triples Tank RPS

  • Defcon 2  - $150 billion, 2 RP - Triples B.F.A.A. RPS
  • Berserker Launcher - $500 billion, 2 RP - Triples M. Launcher RPS
  • Raid Squad - $750 billion, 2 RP - Doubles Aircraft RPS
  • Full Blown - $1.5 trillion, 2 RP - Doubles Chopper RPS
  • War Veteran - $100 billion, 2 RP - Doubles base XP
  • HyperCarrier - $50 billion, 5 RP - Reduces Carrier respawn by five seconds

  • High Command’s School - $500 billion, 2 RP - Doubles Soldier RPS
  • Explosive Ammo - $550 billion, 2 RP - Doubles Bazooka RPS
  • Mortar Board - $600 billion, 2 RP - Doubles Mortar RPS
  • THX2276 Engine - $650 billion, 2 RP - Doubles Jeep RPS
  • Handy Andy - $700 billion, 2 RP - Doubles A.A. Jeep RPS
  • Turbo Quadrigun - $800 billion, 2 RP - Doubles Tank RPS

  • DefCon 1  - $3 trillion, 2 RP - Doubles B.F.A.A. RPS
  • Aka Huroku - $6 trillion, 2 RP - Doubles M. Launcher RPS
  • Death Squad - $10 trillion, 2 RP - Doubles Aircraft RPS
  • Total Recall - $20 trillion, 2 RP - Doubles Chopper RPS
  • Alien Intelligence - $100 billion, 2 RPS - Triples XP given by Carriers
  • Alien Treasury - $10 trilllion, 2 RP - Increases troop RPS by 50%

  • African Support - $2 trillion, 2 RP - Increases troop RPS by 20%
  • SA Support - $3 trillion, 2 RP - Increases troop RPS by 20%
  • Australian Support - $5 trillion, 2 RP - Increases troop RPS by 25%
  • Asian Support - $6.5 trillion, 2 RP - Increases troop RPS by 25%
  • European Support - $8 trillion, 2 RP - Increases troop RPS by 35%
  • NA Support - $9 trillion, 2 RP - Increases troop RPS by 40%

  • Clickduction - $15 billion, 2 RP - Increment per click is doubled
  • Gotta click’em All - $15 trillion, 2 RP - Base per click receives +10% of RPS
  • The Achiever - $50 trillion, 2 RP - Receive RPS bonus equal to the number of Achievements unlocked
  • SupplyBox - $100 trillion, 2 RP - Reduce supply crate cooldown by five minutes
  • Alien Carrier Jammer - $1 Trillion, 2 RP - Carriers are stronger, and give more money / XP
  • Auto-Aim Missile - $100 trillion, 2 RP - Global aliens killed added to Bazooka RPS

  • Alien Technology - $400 trillion, 4 RP - Increase troop RPS by 5% of total
  • Preposterous Speed - $10 trillion, 2 RP - Receive your level multiplied by 25 XP per second
  • War Expertise - $15 trillion, 3 RP - Base XP is doubled
  • Cli-Force - $100 trillion, 3 RP - Increment per click is doubled
  • Alien Tech Factory - $550 trillion, 4 RP - Increase troop RPS by 5% of total
  • Mobile Suit Mortar - $300 trillion, 2 RP - Carriers killed times 25 added to Mortar RPS

  • Black Market - 1 RP - Receive money equal to 300 times your current RPS
  • Black Market Bundle - 10 RP - Receive money equal to 3,600 times your current RPS
  • Tech Factory Upgrade - $650 trillion, 4 RP - Increase troop RPS by 5% of total
  • War of the Worlds - $800 trillion, 3 RP - Adds 10 aliens to the total on the screen
  • Super Jammer - $900 trillion, 3 RP - Doubles the strength of Carriers
  • DeJeepean - $600 trillion, 4 RP - Jeep RPS increases by amount of global time played; adds 60 RPS every minute thereafter

  • Alien Knowledge - $2 quadrillion, 4 RP - Doubles the XP granted by Carriers
  • Gaussian Research - $950 trillion, 5 RP - Increase troop RPS by 5% of total
  • Click Eastwood - $1 quadrillion, 4 RP - Increment per click is doubled
  • Gaussian Development - $6 quadrillion, 6 RP - Increase troop RPS by percentile based on current Rank
  • ???
  • Direct Orders - $800 trillion, 4 RP - A.A. Jeep receives RPS bonus equal to your Rank level times 100

  • Gaussian Bullets - $3 quadrillion, 4 RP - Increase troop RPS by 5% of total
  • ???
  • ???
  • The Experienced Achiever - $3.5 quadrillion, 4 RP - Achievement bonuses are ten times more effective
  • Weak Spot - $4 quadrillion, 4 RP - Speedsters give two RP rather than one when defeated
  • TanKing - $1.5 quadrillion, 4 RP - Tank RPS receives RPS bonus equal to your total number of troops times 100 multiplied by your Rank level

  • Gaussian Suit - $4 quadrillion, 4 RP - Increase troop RPS by 5% of total
  • Tractor Beam - $5 quadrillion, 4 RP - Reduces Speedster movement speed
  • Magnetic Field - $6 quadrillion, 4 RP - Filchers linger on the screen for longer
  • Yellow Knowledge - $1 quadrillion, 2 RP - Yellow supply boxes provide XP as well as cash
  • Gaussian Missiles - $5 quadrillion, 4 RP - Increase troop RPS by 5% of total
  • Since Day 1 - $3 quadrillion, 4 RP - B.F.A.A. receives RPS bonus equal to ten times your XP

  • Crazy Veteran - $1.5 quadrillion, 3 RP - Increment per click is doubled
  • Technology Dissected - $10 quadrillion, 4 RP - Filcher now gives 1 RP for every 15 clicks
  • Gaussian Engines - $6.5 quadrillion, 4 RP - Increase troop RPS by 5% of total
  • Ludicrous Speed - $10 quadrillion, 4 RP - Receive XP equal to your level times 25 per second
  • Gaussian Factory - $15 quadrillion, 4 RP - Increase troop RPS by 10% of total
  • Missile Command - $5 quadrillion, 4 RP - M. Launcher RPS receives multiplier bonus equal to your Rank level plus one
Gaussian Upgrades

The following upgrades must be purchased with Gaussian Points (GP). You can purchase GP by handing in 10 RP per GP. These upgrades are under development, and probably subject to change.

  • Gaussian Condenser - Compresses 10 RP to make one GP
  • Gaussian Soldier - 30 quadrillion, 1 GP - Triples Soldier RPS
  • Gaussian Bazooka - 40 quadrillion, 1 GP - Triples Bazooka RPS
  • Gaussian Mortar - 50 quadrillion, 1 GP - Triples Mortar RPS
  • Gaussian Jeep - 60 quadrillion, 1 GP - Doubles Jeep RPS
  • Gaussian AA Jeep - 70 quadrillion, 1 GP - Doubles AA Jeep RPS

  • Gaussian Mega Condenser - Compresses 100 RP to make one GP
  • Gaussian Tank - 80 quadrillion, 1 GP - Doubles Tank RPS
  • Gaussian B.F.A.A. - 90 quadrillion, 1 GP - Doubles B.F.A.A. RPS
  • Gaussian M. Launcher - 100 quadrillion, 1 GP - Triples M. Launcher
  • Gaussian Aircraft - 110 quadrillion, 1 GP - Doubles Aircraft RPS
  • Gaussian Chopper - 120 quadrillion, 1 GP - Doubles Chopper RPS

  • Eclickse - 100 quadrillion, 1 GP - Increment per click is doubled
  • Mega Jammer - 200 quadrillion, 2 GP - Carrier strength is doubled
  • Weaker Spot - 150 quadrillion, 1 GP - Speedsters drop 3 RP when clicked
  • Pillaging the Pillager - 150 quadrillion, 1 GP - Filcher drops 2 RP every 15 clicks
  • Planar Disrupt - 250 quadrillion, 2 GP - RPS receives 15% of RPS total as an extra bonus
  • Black Market <Gaussian> - 10 GP - Gain resources equal to 40,000 times current RPS
Crates

Every now and then (roughly once every ten minutes, if my estimations are correct) a supply crate will fall out of the sky. If clicked, a supply crate will provide you with a substantial bonus. They're among the rarest occurrences in Save the Earth - The Incremental, and you need to be watching your screen closely to catch one in the act. Supply bonuses can provide the following:
  • A x10 or x20 bonus to your cash and experience for defeating aliens - you'll know these crates are in effect if the sky changes colour (either deep blue or a lighter pink)
  • A large amount of money
  • A large amount of experience
The effects of multipliers last for about 30 seconds before lapsing, so you'll want to make the most of the effect while it lasts. Defeating aliens - particularly Carriers - becomes a priority.

A cluster of aliens, floating above a sea of military troops in Save the Earth - The Incremental
A cluster of aliens, floating above a sea of military troops in Save the Earth - The Incremental
Enemies

- Carriers provide experience and money, and appear often
- Small fliers provide one RP, and appear infrequently
- Filchers provide a lot of experience and money when tapped, and appear rarely
- Motherships provide a ton of experience and money when tapped, becoming incrementally more valuable with each click, and appear every 2,000 or so kills

Ranks

Every time you proceed through a game of Save the Earth, you have the option of purchasing a Rank (and it's an option you should exercise). Consisting of four pieces that are incrementally more expensive, Ranks provide a permanent bonus to your RPS. This bonus is the only thing that carries over between games when you hit the reset button. Do not forget to purchase a full rank before you reset. Otherwise, what was the point?
  • Rank 1 - Private - $2 billion, $7.38 billion, $9.11 billion, $11.52 billion - +2% to all RPS permanently
  • Rank II - Private First Class - $14.9 billion, $19.63 billion, $26.24 billion, $35.51 billion - +4% to all RPS permanently
  • Rank III - Lance Corporal - $48.49 billion, $66.65 billion, $92.08 billion, $127.68 billion - - +6% to all RPS permanently
  • Rank IV - Corporal - $177.52 billion, $247.3 billion, $344.98 billion, $481.75 billion - +8% to all RPS permanently
  • Rank V - Sergeant - $673.22 billion, $941.27 billion, $1.32 trillion, $1.84 trillion - +10% to all RPS permanently
  • Rank 6 - Staff Sergeant - $2.58 trillion, $3.61 trillion, $5.05 trillion, $7.07 trillion - +150% to all RPS permanently
  • Rank 7 - Gunnery Sergeant - $9.89 trillion, $13.85 trillion, $19.39 trillion, $27.14 trillion - +175% to all RPS permanently
  • Rank 8 - Master Sergeant - $38 trillion, $53.19 trillion, $74.27 trillion, $104.26 trillion, - +200% to all RPS permanently
  • Rank 9 - First Sergeant - $174 trillion, $204.34 trillion, $280ish trillion, $400.5 trillion (can somebody verify these? I was really tired and forgot to write them down in time, apparently) - +225% to all RPS permanently
  • Rank 10 - Master Gunnery Sergeant - $560.7 trillion, $784.97 trillion, $1.1 quadrillion, $1.54 quadrillion - +250% to all RPS permanently
  • Rank 11 - Sergeant Major - $2.15 quadrillion, $3.02 quadrillion, $4.22 quadrillion, $5.91 quadrillion - +275% to all RPS permanently
  • Rank 12 - Second Lieutenant - $8.27 quadrillion, $11.58 quadrillion, $16.22 quadrillion, $22.71 quadrillion - +300% RPS to all RPS permanently
  • Rank 13 - First Lieutenant - $31.79 quadrillion, $44.5 quadrillion, $62.3 quadrillion, $87.23 quadrillion - +325% to all RPS permanently
  • Rank 14 - Captain - $122.12 quadrillion, $170.96 quadrillion, $239.35 quadrillion, $335.09 quadrillion - +350% to all RPS permanently
  • Rank 15 - Major - $469.12 quadrillion, $656.77 quadrillion, $919.48 quadrillion, $1.29 quintillions - + 375% to all RPS permanently
  • Rank 16 - Lieutenant Colonel - $1.8 quintillion, $2.52 quintillion, $3.53 quintillion, $4.95 quintillion - +400% to all RPS permanently