Idle Monster TD 9+

Battle endless evil robots‪!‬

Iron Horse Games LLC

Designed for iPad

    • 4.7 • 2.4K Ratings
    • Free
    • Offers In-App Purchases



Battle endless robots in Idle Monster TD! Use epic monsters as your idle towers to auto battle endless swarms of enemies.

Over 2 million players!

Protect the... monsters? As the commander of the United Monsters Alliance, you’ll defend your homeland from menacing machines in Idle Monster TD.

This delightful take on tower defense flips the script, putting you in charge of helpful creepy-crawlies trying to stop robot invaders from pummeling your base. Strategically place allies like Sea Stallion for extra-speedy attacks, or use Firefly for heavier damage. And if things get real dicey, just wipe the map clean with a firestorm spell!

Eradicating bots gives you upgrades to bolster power, speed, and other stats - and the more bots you obliterate, the more monsters you’ll unlock. Idle Monster TD’s menagerie is filled with awesome beasts, like cute water sprites and scorching fire devils. Discovering new creatures is part of the fun.

Like any loyal pal, Idle Monster TD takes care of itself when you’re away. Come back in a few days to claim gold and power up your defenses. Those robots don’t sleep—but neither do your monsters.

- Unlock 44 unique monsters of different elements (Water, Air, Earth, and Fire), all of which have different skill sets that make tower synergy crucial to success.
- Strategize by placing up to 10 monsters at a time. Determining the most effective combination of their elemental skills and passive boosts will keep you entertained and speculating for weeks!
- Play through 8 different maps, each requiring different strategies to defend most efficiently.
- Bi-weekly PvP tournaments give this casual game a competitive edge.
- Discover countless upgrades, research, spells, artifacts, relics, technology, and more to level up with a variety of different resources.
- Several rewarding mini-games, such as Drone Swarms, Cargo Ships, and Tech Ships.
- Non-stop, endless gameplay!
- Fantasy RPG-based world and classes.
- Complete tons of daily missions and achievements.
- Offline gold earnings reward you while the game is closed!
- Fun and cute pixel artwork.

Idle Monster TD is a perfect blend of the Idle and Tower Defense genres. The game is endless and can mostly play itself without you watching. However, an immense amount of strategy is required to play efficiently and place well against your peers on the leaderboards. Go on an epic never-ending quest, explore a fantastic world, battle robots and monsters, and defeat epic bosses in Idle Monster TD!

What’s New

Version 108

- Performance improvements.
- Bug fixes.

Ratings and Reviews

4.7 out of 5
2.4K Ratings

2.4K Ratings

MrSchmidtFace17 ,

I love it, I just have some suggestions.

This is honestly one of the best games I’ve ever played, My highest wave is 1499 so you know that I both love the game and I’m soooooo close to unlocking the last monster pack. I have a few suggestions though: first, after around 1000 waves it becomes pointless to prestige again because all the effort to get back to that point is no longer worth the amount of prestige points offered, I think either the prestige points earned should get a giant boost or the upgrades from prestige points should be much cheaper. Second, I think one of the ads rewards should be one minute of no elemental shields because that would be a major help (and I say that with having maxed out percentage of enemies without shields and maxed out percent of enemies temporarily losing elemental shield on Squidler). Third and final suggestion, is to increase experience earned per kill because I have only one monster that is above level 100 and like I said earlier, my highest wave is 1499. Also, quick question; if Earsy Rider uses its turn around ability and the enemy enters Squidlers range while turned around, can its elemental shields still be taken down?

JodyFin ,

It’s a fun game

I appreciate how they don’t have constant forced ads; rather it’s an optional ad that gives you a gift. The in app prices seem steep, but I see it as a necessity to help keep forceful ads at bay. Or you can just stay as a Free to play player. It’s a grind, but if you’re here, then that’s what you already want. An idle TD game that feels almost infinite, taking up 10 minutes of time or even hours. With a variety of ways to power up your monster using Essence or gems, also prestige points. You gain essence by beating every 10th level and from bosses I presume, my highest wave is only 190, so I’m still very new. Gems can be earned from completing challenges, while Prestige points can be amassed by going up in prestige. Also there are buyable bundles/packs of goodies. Good game.

Edit/tip: save up gems for 2x gameplay speed. It takes about two and a half days to earn 500 through achievements, and gift ads, it might even take less time tbh. Since I wasn’t too avid about playing, but I did let it play through the night as I slept. 100% worth it

hilnoh ,

Good game with great potential

So I just dowloaded this game yesterday and it’s very addicting. Only problem I have is that the the only thing you get while afk is gold. The timers don’t reset or continue to count down unless you’re in game. Now the skills are one thing since they don’t take a long time, but things like the cargo carrier which take about four hours are a different story. I don’t know why the devs would think people would want to sit in game for 4 hours or more. Now I know there are upgrades that minimize the amount of time needed for the ships and drones but the fact that you have to sit in game for like 12+ hours at least to get those upgrades is pretty ridiculous. This game is good but could be much, much better with one fix. Besides that the music, characters, and upgrade system along with other things make this game very good. This game has crazy potential and the only thing holding it back is that the game isn’t very much about the afk aspect since you have to sit there for hours to actually get good stuff. Anyway highly recommend but be ready to put in a good amount of time if you want to make it in this game.

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