Underdark:Defense

Name: Underdark:Defense
Rating: 4.8 (3551 reviews)
Author: SeungHo Chung

Tactical Tower Defense

Free · In‑App Purchases · Designed for iPad

3.6K Ratings
Ages

9+
Years
Category

Strategy
Developer

SeungHo Chung
Language

EN
+ 4 More
Size

481.7
MB

Defend the Flame from the dark! Level up, strategically place towers, and choose buffs to grow stronger. Keep the light alive! Defend the Eternal Flame: Experience the thrill of defending the flame from hordes of dark forces that besiege it! Feel the exhilaration as you clear stages, with each victory more satisfying than the last. One-Handed Gameplay: Enjoy easy-to-master controls, designed for one-handed play. Perfect for strategic fun anytime, anywhere. Customize Your Defense Strategy: Select buffs and strategically place towers to forge your path of resistance. As you level up and choose your growth buffs, your defense becomes an impenetrable fortress. Heroic Stand: Choose your guardians to stand against the night. Each hero brings unique abilities to the battlefield. Earn trophies, level up, and enhance your heroes to ensure the flame flickers on through the darkest nights!

Events

PREMIERE

New Hero [Gumiho] Arrives!

Normally disguised as a human, she regains her true fox form and deadly power after consuming a liver.

Ratings & Reviews

4.8

out of 5

3.6K Ratings

Editors’ Choice

Hold back the hordes with cannons, ballistae, and your own hero in this action-packed tower defense game.
Great game, reasonable progression
11/27/2024

JeffSchwarz
Short version: great game, great progression speed, very fun, good design, not a cash grab. I love it and praise the developer. Long version: I’m really impressed with this game, it’s fun and the progressing rate is very reasonable. There is the option to watch adds to speed things up a bit, but it doesn’t make it painfully slow if you don’t watch adds and none are forced on you, so it really feels optional and like you’re actually purchasing a benefit, not removing an annoyance. On top of that, it is a permanent add removal, but the “watch an add to get x” options stay and just become free. So I absolutely paid the reasonably priced remove adds forever button. It’s no different than if I had to pay that price to buy the game, except I got to trial for free and there’s extra benefits. I’m impressed, it’s an actual fun game, not a cash grab, and I hope this developer makes more, this is a rare find today and I’m super pleased.

Developer Response
Thank you so much for your thoughtful and positive review! We’re thrilled to hear that you’re enjoying the game and appreciate the progression speed and system design. Your feedback on the ad system aligns perfectly with the direction we aim to take, and it’s incredibly encouraging. We’ll continue to work hard to deliver even better content and improvements to meet your expectations. Thank you once again for your valuable feedback and support!
Great game, reasonable progression
11/27/2024

JeffSchwarz

Short version: great game, great progression speed, very fun, good design, not a cash grab. I love it and praise the developer. Long version: I’m really impressed with this game, it’s fun and the progressing rate is very reasonable. There is the option to watch adds to speed things up a bit, but it doesn’t make it painfully slow if you don’t watch adds and none are forced on you, so it really feels optional and like you’re actually purchasing a benefit, not removing an annoyance. On top of that, it is a permanent add removal, but the “watch an add to get x” options stay and just become free. So I absolutely paid the reasonably priced remove adds forever button. It’s no different than if I had to pay that price to buy the game, except I got to trial for free and there’s extra benefits. I’m impressed, it’s an actual fun game, not a cash grab, and I hope this developer makes more, this is a rare find today and I’m super pleased.
Developer Response 12/11/2024
Thank you so much for your thoughtful and positive review! We’re thrilled to hear that you’re enjoying the game and appreciate the progression speed and system design. Your feedback on the ad system aligns perfectly with the direction we aim to take, and it’s incredibly encouraging. We’ll continue to work hard to deliver even better content and improvements to meet your expectations. Thank you once again for your valuable feedback and support!
Time Is Everything
09/02/2025

red-wolf00
this is my second account ive had to create to play this game, im not bothered by having to create a new account but what does bother me is i forgot the reason i uninstalled in the first place. now i remember why thanks to my second play through. the random crashes! nothing worse than spending 10-15+mins in a game and then all of a sudden it crashes and when you go to start back up, there is no continue game. to me this is what kills the fun for me. no rewards or anything to show for it just treated as the player gave up. the game is fun, the challenges are plenty and the difficulty ramps up slowly but not to a point where its boring. the game is a fun game but because of the random crashes and no way to continue the match when that happens, i cannot see myself playing this game anymore until there is a form of support for the player back end. to me time is the most important element. even if the it wasnt a crash, it would be nice to be able to pick back up later and continue playing. especially considering a internet connection is required to play.
Time Is Everything
09/02/2025

red-wolf00

this is my second account ive had to create to play this game, im not bothered by having to create a new account but what does bother me is i forgot the reason i uninstalled in the first place. now i remember why thanks to my second play through. the random crashes! nothing worse than spending 10-15+mins in a game and then all of a sudden it crashes and when you go to start back up, there is no continue game. to me this is what kills the fun for me. no rewards or anything to show for it just treated as the player gave up. the game is fun, the challenges are plenty and the difficulty ramps up slowly but not to a point where its boring. the game is a fun game but because of the random crashes and no way to continue the match when that happens, i cannot see myself playing this game anymore until there is a form of support for the player back end. to me time is the most important element. even if the it wasnt a crash, it would be nice to be able to pick back up later and continue playing. especially considering a internet connection is required to play.
Just what I've been looking for!
11/16/2025

Leaf Locrian
I've been bouncing between mobile games for a while trying to find something I could dump some time into. This game has finally hit all of the bases that I want in a game. It has gradual progression so you can gear up to beat tougher levels. It has tower defense so there's a decent amount of strategy into routing enemies cleverly. It doesn't force ads, only offering them for rewards which I appreciate. There's also a cute art style and it's INCREDIBLY gentle on my phone battery. It's easy to pick up when you just have a couple minutes to kill between tasks, like waiting to be called for an appointment or a short car ride (obviously as a passenger). Progress saves when closing the game so you can hop back in to where you left off. Best mobile time killer since Balatro for me!
Just what I've been looking for!
11/16/2025

Leaf Locrian

I've been bouncing between mobile games for a while trying to find something I could dump some time into. This game has finally hit all of the bases that I want in a game. It has gradual progression so you can gear up to beat tougher levels. It has tower defense so there's a decent amount of strategy into routing enemies cleverly. It doesn't force ads, only offering them for rewards which I appreciate. There's also a cute art style and it's INCREDIBLY gentle on my phone battery. It's easy to pick up when you just have a couple minutes to kill between tasks, like waiting to be called for an appointment or a short car ride (obviously as a passenger). Progress saves when closing the game so you can hop back in to where you left off. Best mobile time killer since Balatro for me!

[Update Details – January 1] New Hero - The Nine-Tailed Fox joins Underdark! - Defeat enemies together with the charming Nine-Tailed Fox! New Stages and Special Notes - Normal stages have been expanded up to Stage 890. - 10 new stages have been added. Events - The 2026 New Year Event begins on January 1 (KST). - The Board Mini-Game begins on January 1 (KST). - The Bingo Event ends on December 31 (KST). Bug Fixes and Improvements - Lava Golem optimization has been applied. - Lava Golem’s Fireball damage and movement speed have been increased. - A Curse Tower tutorial has been added to Stage 21.

Version 3.0.4

12/31/2025

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