Mob Control

Forty seconds, one cannon and a tower with fifteen thousand HP

I opened this game because of the cover image with a giant X500 on it, assuming it would be another tap-for-fun game I'd drop after a few minutes. The first battle really was easy.

Just keep your finger on the screen and blue troops pour out in a long line, squeeze through a doubling gate and bash down a wooden door without any thought at all. By the third battle, the tower in front of me showed fifteen thousand HP.

The troops I fired only scratched off a few hundred per wave, while the enemy army poured down the next lane very quickly. They reached my cannon, and the screen showed a defeat message along with a bright green revive button.

How a battle plays out

You hold a cannon at the bottom edge of the screen, slide sideways to pick a lane, and keep your finger down to fire troops nonstop. The troops run straight ahead, and along the way there are gates marked X2, X3 or X10; pass through one and your troop count multiplies by exactly that much.

The clever part is that each gate only works once per pass, so sending ten troops through an X10 gate pays far better than sending a hundred through an X2. Some boards also place a red subtraction gate right next to a multiplier, and firing into it by mistake wipes out half your mob.

On the far side of the map, your opponent also has a cannon and also fires troops down toward you, so the two streams meet in the middle of the road and fight on the spot. Whoever has troops left keeps going and slams into the other side's tower, while whoever lets enemy troops reach their own cannon loses on the spot.

Hold your finger in one place long enough and the cannon turns gold and shows a release prompt; let go and a much bigger wave of troops fires straight up. The settings also have an auto-fire switch for anyone who doesn't want to keep a finger down.

I tried it, and it really is more relaxing, but it fires rather aimlessly and often wastes the good gates. So I went back to holding my finger down to be safe.

Ten cannons, and you only get to hold one

Outside of battle is a storehouse called the Armory, which lines up ten different cannons as cards. At the start you only have the Single Shot, which fires one unit at a time.

Rapid Fire, Shotgun, Sniper and Big Bertha all sit behind gold padlocks, each with a line spelling out what you have to do to unlock it. Every cannon and every troop type is a card with its own level.

Leveling up takes gold plus duplicate cards collected from the packs you open after battles. One level on the Single Shot only moves its fire rate from 2.60 to 2.65 troops per second, which sounds tiny, but a few dozen levels add up to a real difference.

Cards also come in color-coded rarities, and card levels go all the way to 75, with two quality upgrades at levels 25 and 50. One look at that number tells you this system is built to keep you going for months, not a few evenings.

Bases, bricks and raiding other people

After a few wins the game opens a base map of your own, with a crumbling town hall, a few empty plots and a brick counter right in the middle. The town hall wants exactly one thousand bricks before it's repaired.

You can't buy bricks with gold, however much gold you have. The only way to earn bricks is to attack other players' bases.

The game matches you with a real account, shows their name and avatar, and lets you fire troops at their door. The deeper you break in, the higher your raid score, and my best haul was over twelve hundred bricks plus nearly six thousand gold in a single battle.

Between raids there are fortress battles against the computer and special boss stages, like the octopus-shaped Krill McKraken, which drops seven thousand six hundred gold when beaten. On top of that runs a season split into five chapters of ten missions each, and the reward at the end of chapter one is the Rapid Fire cannon.

And this is where the game starts eyeing your wallet

The base has a Fire rate upgrade button, and since that stat affects every cannon you hold, it's the best thing to pour gold into. Its first level costs one and a half thousand.

Each level adds another five hundred, and by level twelve the game asks for fourteen thousand gold for a single tap. Gold drops after every win, but even a great battle only gives you a few thousand.

Cannon cards and troop cards eat that same gold, so you're always short. Do the simple division and raising one cannon to a decent level takes a few dozen wins, and that's before counting the nine cannons still locked.

The game doesn't hide what it's selling either. After each win there's a wheel that doubles or triples your loot in exchange for watching an ad, and between stages full-screen ads squeeze in on their own.

The shop offers a VIP membership, an Elite membership and a few starter packs, including a Premium pack at sixty percent off with two and a half million gold, fifty card packs and permanent ad removal. On the US Google Play store, the game's purchases run from $0.84 to $399.99 per item.

The mod removes exactly that gold button

The mod here has just one switch, called Freeze resources. You tap the floating MOD button in the left corner of the screen, flip the switch, and reopen the game once, and that's it.

From then on the game still grants exactly what you just bought, and only the gold deduction gets blocked. I tested it right on the Fire rate button, which was at level six at the time, with nineteen thousand seven hundred gold in the wallet.

Six taps in a row took it straight to level twelve, while the total I should have paid was thirty-one thousand five hundred, more than I even had. I backed out and came back in, and the wallet still read exactly nineteen thousand seven hundred, with level twelve still in place.

Cannon cards in the Armory behaved the same way: I raised the Single Shot two more levels and the gold went right back to where it was. After another game restart every level I'd bought was still there, so this isn't one of those fake numbers that show up for fun and then vanish.

Three things worth knowing up front, so you don't expect the wrong thing:

• The number on the gold bar still drops the moment you tap buy, even into negatives, but leave and come back and it returns to the old number.
• Base-building bricks aren't covered by the freeze, so to fix the town hall you still have to raid your way to a thousand of them.
• The real-money shop doesn't open here, so the mod has no way of granting you those paid packs.

What feels great and what grates when you really play

The best part is how short the battles are, usually under a minute, yet there's still room to think instead of tapping blindly. The rounded art is cheerful, and troops streaming along in a river look great.

Watching a handful of troops turn into a whole sea after three gates is hard to get tired of. The annoyances are real too, though, because the ads come thick and fast, and everything funnels into one kind of gold, so you're always short.

The game is English-only with no language setting, and there's very little text in it anyway. One more thing to know up front is the dialog box asking you to rate the game.

It pops up now and then and sometimes can't be tapped; when that happens, close the game and open it again and it's gone, with no progress lost. Apart from that, I played a whole session without a single freeze.

On Google Play the game holds 4.3 stars from close to a million reviews, and its downloads have passed the hundred-million mark.

So who should download it

If you're looking for something to tap while you wait for dinner or the bus, this is a great fit: open it, play a few battles, and put the phone away. It doesn't make you learn anything and there's no long-winded story.

Yet there's still enough depth to make you come back and see how the next cannon unlocks. And if you downloaded it before and gave up because you were stuck in one place for lack of gold, the mod removes exactly the button that blocked you.

Flip the switch, upgrade Fire rate and the cards in the Armory to your heart's content, then go back to the very stage that made you give up. This time, see how long it holds out.