Comparison

Merge Loop vs Rat Killer Robot Invasion

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

Head to head
About

Merge Loop

Features
Read full description

It's time to storm the keep and lead your soldiers to victory! Before you take the castle, you must create stronger knights to topple the evil army holding it captive. Loop around the track with your army towards the stronghold, and along the way managing & buying more units, then merge them to create strong soldiers before upgrading them into a superior army to destroy your foe! Loop around the track again and continue upgrading your units, merging them and buying more as you near the fort. Can you strategise to use the right method of action and decide what's best to spend your in-game currency on? Will you invest in upgrades for your troops? Or will you hire more mercenaries to merge together? Do what you can to avoid falling before your enemy and losing on the battlefield! A clash with the enemies is the way to find out as you merge your army into the ultimate fully geared battalion at max level! HOW TO PLAY Hold down to walk around the loop and let go to stop at buy stations. Once ready to move, hold down again to continue around the track. Your soldiers will automatically attack once near enemies. FEATURES Awesome battles! Lots of upgrading and merging your troops. Create the ultimate knight to destroy the enemy army. Easy to learn but with depth and mastery. Gain more power by upgrading, merging and buying more units with in-game cash! Free to Play with support for lots of devices. JOIN THE FULL FAT COMMUNITY Like: http://facebook.com/fullfatgames

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

Screenshots

Merge Loop4 screens
Rat Killer Robot Invasion4 screens

Verdict

The call

The clearest difference is in-app purchases: Merge Loop at none against Rat Killer Robot Invasion's 17. Rat Killer Robot Invasion's advantage is update cadence (every 10 days vs monthly). On price, ads, device support and iOS requirement 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. Merge Loop asks for nothing beyond the download.

UpkeepUpdate frequency

Merge Loop ships an update monthly, Rat Killer Robot Invasion every 10 days. The most recent releases landed on October 13, 2026 and October 22, 2026 respectively.

Scorecard2 real differences · 8 level
Merge Loop versus Rat Killer Robot Invasion: the parameters behind the verdict, then further details
ParameterMerge LoopRat Killer Robot Invasion
PriceFreeFree
Rating—4.6 (2K ratings) — better
Positive reviews—31.1% of reviews
Number of ratings—2K — better
Update frequencyMonthlyEvery 10 days — better
AdsYesYes
In-app purchasesNo — betterYes
Monetization—Free with in-app purchases
DevicesiPhone, iPad, iPodiPhone, iPad, iPod
Requires iOS13.012.0 — better
Further details — not scored
Size117 MB353 MB
Age rating12+9+
DeveloperFull Fat Productions LtdTapNation

Bugs and requests

Merge Loop

Not enough reviews yet to summarise bugs or 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

In-app purchases

None

Merge Loop

No 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

Questions

Is Merge Loop free?
Merge Loop is free to download, with no in-app purchases.
Is Rat Killer Robot Invasion free?
Rat Killer Robot Invasion is free to download, with in-app purchases available.
Do Merge Loop or Rat Killer Robot Invasion have ads?
Both Merge Loop and Rat Killer Robot Invasion show ads.
Which is updated more often, Merge Loop or Rat Killer Robot Invasion?
Merge Loop ships an update monthly, and Rat Killer Robot Invasion every 10 days. Most recently, Merge Loop was updated on October 13, 2026 and Rat Killer Robot Invasion on October 22, 2026.

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