Comparison

Rat Killer Robot Invasion vs Bullet Engineer

Price, ratings, monetisation and update history for both games, side by side — with what reviewers say about each.

Head to head
About

Rat Killer Robot Invasion

Embark on an epic quest to exterminate waves of invading rats with futuristic weapons. Collect in-game currency to unlock new zones, upgrade your robot companion, and customize its appearance. Explore diverse worlds and face challenging puzzles and boss battles.

Highlights
  • Rat extermination action
  • Robot customization
  • Weapon collection and upgrades
  • Diverse world exploration
  • Puzzles and boss battles
  • Collect money and gems
Features
Read full description

Rat Killer Robot Invasion: Save the World! The world is under siege by a relentless rat army! It's up to you, the ultimate Rat Killer Robot, to restore peace and cleanliness. Are you up for the challenge? Rat-Blasting Action: Armed with powerful weapons, embark on an epic quest to exterminate the rat invaders. Zap, blast, and splat your way through waves of rats to protect the world! Collect & Upgrade: While on your rat-slaying adventure, gather valuable money and glittering gems. Use them to unlock new zones, buy futuristic weapons, and upgrade your trusty robot companion. Customize your robot with cool, eye-catching designs. Explore Diverse Worlds: Travel through various zones, each with unique challenges and rat foes. From city streets to hidden sewers, the battle against the rat invasion rages on! Game Features: - Non-stop rat extermination action! - Endless customization options for your robot. - A plethora of weapons to choose from. - Exciting puzzles and epic boss battles. - Explore different zones and unlock secrets. - Collect money, gems, and robot parts. - Free to play! Join the Rat Killer Robot Invasion and be the hero the world desperately needs

About

Bullet Engineer

Features
Read full description

Bullet Engineer is a fast-paced pixel-art roguelike shooter where every run unlocks new weapons, shells, upgrades, trophies, and prestige ranks. Fight endless waves of enemies, complete missions, master powerful shell types, and climb through the prestige system to become the ultimate Bullet Engineer. Features: • Fast arcade gameplay • Unique shell upgrades • Prestige progression • Daily missions • Weekly challenges • Unlockable trophies • Pixel cyberpunk visuals • Offline gameplay

Screenshots

Rat Killer Robot Invasion4 screens
Bullet Engineer4 screens

Verdict

The call

The clearest difference is in-app purchases: Bullet Engineer at none against Rat Killer Robot Invasion's 17. Rat Killer Robot Invasion's advantage is device support (3 vs 1) and iOS requirement (12.0 vs 18.6). On price, update cadence and ads there is nothing between them.

Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS

CostPrice · In-app purchases · Ads · Monetization

Both are free to download. Rat Killer Robot Invasion sells 17 in-app purchases, starting at $4.99 per 7 days. Bullet Engineer asks for nothing beyond the download.

UpkeepUpdate frequency

Rat Killer Robot Invasion ships an update every 10 days, Bullet Engineer weekly. The most recent releases landed on October 22, 2026 and October 12, 2026 respectively.

Scorecard3 real differences · 7 level
Rat Killer Robot Invasion versus Bullet Engineer: the parameters behind the verdict, then further details
ParameterRat Killer Robot InvasionBullet Engineer
PriceFreeFree
Rating4.6 (2K ratings) — better—
Positive reviews31.1% of reviews—
Number of ratings2K — better—
Update frequencyEvery 10 daysWeekly — better
AdsYesYes
In-app purchasesYesNo — better
MonetizationFree with in-app purchases—
DevicesiPhone, iPad, iPod — betteriPhone
Requires iOS12.0 — better18.6
Further details — not scored
Size353 MB11 MB
Age rating9+4+
DeveloperTapNationIbrahim Al-Dossrai

Bugs and requests

Rat Killer Robot Invasion

Reported bugs

8 issues
  • Character flipping upside down or flying across the board
  • NPCs getting stuck in portals or on walls
  • Incorrect item/reward drops from chests
  • Launching player off the screen
  • Robot unable to keep legs on the ground and rolling around
Show 3 more
  • Collector robot not depositing cash
  • Portal progression not working as intended
  • Crashes on launch

Requested features

4 requests
  • Optimize performance and fix bugs
  • Improve game balance and progression
  • Add more content and features
  • Provide better customer support

Bullet Engineer

Not enough reviews yet to summarise bugs or requests.

In-app purchases

17 purchases

Rat Killer Robot Invasion

Subscriptions3
  • VIP Membership - Weekly$4.997 Days
  • Elite Membership - Weekly$8.997 Days
  • Elite Membership - Monthly$24.991 Month
One-time14
  • Skip It - Small Pack$0.99
  • One Time Offer$1.99
  • Handful Of Crystals$1.99
Show 11 more
  • Bunch Of Crystals$4.99
  • Skip It - Medium Pack$8.99
  • Pile Of Crystals$8.99
  • Rats Pass$9.99
  • Small Bundle$11.99
  • Master Mode$15.99
  • Starter Pack$15.99
  • Medium Bundle$24.99
  • Limited Offer Pack$29.99
  • Premium Offer$39.99
  • Crate Of Crystals$89.99
None

Bullet Engineer

No in-app purchases

Questions

Is Rat Killer Robot Invasion free?
Rat Killer Robot Invasion is free to download, with in-app purchases available.
Is Bullet Engineer free?
Bullet Engineer is free to download, with no in-app purchases.
Do Rat Killer Robot Invasion or Bullet Engineer have ads?
Both Rat Killer Robot Invasion and Bullet Engineer show ads.
Which is updated more often, Rat Killer Robot Invasion or Bullet Engineer?
Rat Killer Robot Invasion ships an update every 10 days, and Bullet Engineer weekly. Most recently, Rat Killer Robot Invasion was updated on October 22, 2026 and Bullet Engineer on October 12, 2026.

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