UnderDark: Defense

We lost our first run of UnderDark: Defense, and it took us a moment to figure out why. The character was still standing, HP still full, monsters still getting hacked apart, and yet the screen already said Defeat.

The explanation sits right underneath, and it spells out exactly what makes this game different from every other tower defense title: the campfire has run out of HP. At the bottom of the cave chamber there's a small fire, and that, not you, is what you have to protect for the whole battle.

You don't die, the campfire does

The arena is a vertical cave chamber seen from above. Monsters spawn at the top edge and walk straight down, while you play a little blue slime carrying an axe, steered with a virtual joystick on the lower half of the screen.

Your character swings automatically in an arc, so there's no attack button, and your job is to stand in the right spot. Each hit deals thirty-three damage, and that number holds in both the tutorial and the first stage.

Killing monsters drops experience gems, and when you collect enough you level up mid-battle; the game pauses and offers three cards. There are two kinds: cards that boost your character's stats, and cards that give you a tower to drag onto the grid on the field.

Once built, towers shoot for you, and they hit far harder than you do. In our first hands-on run, the end-of-battle stats credited the character with fifteen percent of the damage and the ballista with eighty-five percent.

And here's where the game is surprisingly decent. The defeat screen shows exactly the same reward box as the victory screen, still paying out experience, red gems and diamonds, still with a double-reward button next to it.

The only thing you lose is the ticket you spent to enter the stage. Tickets are this game's stamina: the tank holds forty, a stage takes three to five depending on where you are, so a full tank lasts about eight runs.

There's no penalty screen, no lost gear, no level drop. In other words, losing in this game only costs you time, not anything you own, and that makes the pace much more pleasant than in most games of the genre.

Unlocks are counted in runs, not levels

The bottom bar has five slots, but at the start only two are open and the other three are padlocked. Tap a padlock and the game tells you plainly that you need ten more runs to open it, while the slot next to it says one more.

We pushed the account to nearly level one hundred with the mod itself, and one padlock is still sitting there. Levels don't buy you content, only the number of trips down into the cave does.

In exchange, higher levels get you better gear by a rather neat detour. Items pulled from chests are tiered by account level, so at level eighty-one all ten items we pulled were level-eighty-one gear.

The cave map is split into four tabs, including an auto-chess mode called Deer Station and a multiplayer tab. Along the bottom of the main screen runs a global chat with real people, the kind where someone just cleared stage twenty or someone just lost ten runs in a row.

Nine minutes without finding a way to close an ad

Ads are plugged into four places here, each with its own cap. In battle there's the button that swaps your three cards, three times per run. At the end of a battle there's the double-reward button. In the shop there are two lines, one for tickets and one for diamonds, each three times a day.

We removed the mod to see how long one real ad lasts, and the answer left us a little stunned. It opened with a TikTok clip of about a minute, then switched by itself to a playable ad for another game, and that ad had no close button in any corner.

We pressed back, tapped all four corners of the screen and even played the mini-game through to its victory screen, and the progress still read one out of ten. After nine minutes we gave up and killed the app. A second try on the ticket button went exactly the same way, and we had to kill the app again.

The mod cuts right there, and cuts almost all of it

The MOD menu has eight switches and we scored all eight. All of them sit in the VIP 1 tier, and you just flip one on in the menu for it to run. With "Skip ads" on, tapping the card-swap button brings up three new cards instantly, and tapping the double-reward button at the end of a battle doubles the reward on the spot with no clip playing.

The damage switch lets you type in the number for each hit. We set five thousand, and the numbers over the monsters really did read 5K, against thirty-three before the mod, and the whole swarm melted in a single swing.

The gold, experience and diamond switches set the base figure on the results screen, then the stage applies its own multiplier, so what you actually receive is usually more than the number you set. The auto-chess coin switch keeps your wallet in the auto-chess cave from going down when you buy cards or reroll the board.

There's exactly one gap we found. "Skip ads" covers the in-battle button and the end-of-battle button, but the ten-ticket line in the shop still plays the full clip, because that one goes through a different path the mod doesn't reach yet.

God mode won't save you from losing

This is the easiest thing to misunderstand in the whole mod, and it goes right back to the campfire from the start of this article. With God mode on, your character stops taking damage; we stood face to face with monsters for minutes and the health bar didn't even bother to show up.

But both times we turned it on, the run still ended with the message that the campfire had run out of HP. Monsters walk around you to hit the fire, and the mod doesn't touch the fire's HP. What it buys you is the right to plant yourself in one spot and fight, not a get-out-of-defeat card.

The battle speed switch needs a word of explanation too. Its slider isn't a multiplier but the time step for each frame, so the bigger the number, the faster the battle runs, and the same number gives different speeds on two different phones. When we timed it, the setting we had came out at about 2.4 times normal speed.

Chests cost more the more you pull, and ad removal is $10.99

The game's shop is split into several tiers, and each one has its own gate. The $2.99 fire weapon pack states clearly that it can only be bought until your account reaches level twenty-five, and only once per account, so it's aimed squarely at newcomers.

The most expensive pack we saw was just under $110 for fourteen thousand diamonds. The permanent ad-removal pack costs $10.99 and comes with a handful of red gems, diamonds, keys and tickets.

The chests have a pretty blunt price curve. At first a single pull costs three hundred red gems and ten pulls cost three thousand, but as soon as we finished a ten-pull, the price board changed to four hundred and fifty for a single pull, and the ten-pull slot turned into a fifteen-pull slot at six thousand seven hundred and fifty.

A million downloads and twelve languages

The game has passed a million downloads and holds about 4.4 stars from more than 71,000 ratings on Google Play, so it has a sizable crowd behind it.

The language list in the options has twelve entries, from Korean, Japanese and Russian to Polish and Hindi, and English is what we played in.

So who should play it

If you like tower defense but you're tired of standing back and watching towers shoot, the way this game has you running, hacking and building towers all at once is a fun mix. Each run wraps up in a few minutes and losing costs nothing but a ticket, so it's great for picking up whenever you have a spare moment.

And if you downloaded it before and quit because of that ad you couldn't close, that's exactly what the mod handles best. Just keep one thing in mind: with God mode on, you still have to keep an eye on the fire behind you.