Resembling Wolfenstein 3D and with gameplay mechanics borrowed from Rogue and Pac-Man, Hammer Bomb dumps you in randomised mazes, yells "SURVIVE THIS," and scampers off to gleefully watch from the sidelines.

From the off, it feels a bit weird. Peering at the chunky graphics, you expect to strafe and shoot Nazis.

But instead, this one's all about swiping as you auto-run, and attempting not to blunder into terrifying bees, crows, goblins, and flying eyeballs.

Avoiding death is usually a case of scarpering, swiping left or right to dart down a corridor, down to make a quick U-turn, or up to jump over the many pits of death some idiot has carelessly dug about the place.

HAMMER TIME!

Before long, you'll chance upon a crystal or a crate. The former boosts your score and XP, but the latter flings gold coins at your face, as well as occasionally heaving up a weapon.

Armed with a hammer, you can smash through cracked walls and nasties, swords are for getting all stabby with, and a bow and arrow offs foes at a distance.

But ammo is short and mostly best left for when you find yourself a stone's throw from an enemy in a dead end (emphasis very much on the ‘dead' when weaponless).

Weapons also come in handy during boss fights, which mostly involve running up to a massive beast, briefly attacking with whatever you have to hand, and then running away like a chicken.

Crates sometimes also provide missions, which are best described as utterly stupid. The app barks orders using throaty samples resembling those from 1980s hit Gauntlet, only instead of suggesting you don't shoot food, the disembodied voice says to hunt it.

In this world of mazes and death, it turns out intrepid explorers must stalk giant cupcakes (in another nod to the Pac-Man series).

Still, grabbing one is rewarding, your XP in the between-level sequence shooting through the roof, riding the wave of your sugar high.

MAP IT TO 'EM

XP is important because it unlocks new goodies to buy with coins collected in-game or (inevitably) through injections of IAP. Most are weapons upgrades, but by level three you'll be able to purchase a radar.

Frankly, the radar should have been in the game from the start, because it's transformative, giving you a means of avoiding the various giant evil things stomping about, simply by glancing at an on-screen map.

It's a rare mis-step in this endlessly replayable (if ultimately not terribly varied) freebie, a game that proves more rewarding the longer you stick with it.

Its fast, frenetic nature is perhaps how people in the 1980s imagined Pac-Man would one day be. Although we doubt they dreamed of being murdered by a giant 3D crow.