They say a hero’s work is never done, and Slayin will make you believe it. Billed as an endless action RPG, this pixelated effort from FDG Entertainment is a fast-paced thrill ride sure to leave your knuckles white.

In Slayin, players must choose from one of 3 classes with which to defend the kingdom: Knight, Wizard, and Knave (though the latter 2 must be unlocked first). Gameplay is deceptively simple and occurs on a wide, open expanse as monsters pour in from all sides. An on-screen controller featuring left and right arrows to move and an action button (used either to jump or cast a spell) are the only controls available with which to fend off the increasingly difficult waves of monsters, including boss fights every 10 levels. Those controls fit in the hand much better on the iPhone, but the iPad is certainly a viable device on which to play the game.

The game’s retro-inspired graphics are more than a fun homage to days gone by. They also portend a retro-style level of difficulty. Levels become frenetic and tense very quickly and will force players to use the coins they collect as monsters perish on various weapons, armor, or health-replenishing food. The management of those funds is probably the most vital skill for a hero aspiring to conquer all 8 bosses. In fact, until players acquire a working knowledge of the various equipment and which pieces mesh best with their playstyle, deep runs into the game are likely impossible.

Gameplay is exciting and well-polished, with an impressive array of enemies and evolving AI patterns. There are a few flaws, however. First, because enemies of most types are spawned at random locations, there are plenty of situations where you must take a hit, through no fault of your own. Worse still, as enemy speed increases later in the game, some enemies will spawn directly below your position or in your path mid-jump, leaving you insufficient time to get out of the way before taking damage. That said, it is rather satisfying to pull off a flawless, flailing jump to get out of a sticky situation and clear half the screen of baddies.

The boss fights in particular are where the game shines, as the pixel art for each is impressive and every monster has rather varied attack patterns. The difficulty ramp of the big bads might be a bit questionable, but each confrontation is a fun change of pace from the regular flow of the game.

Though death means losing all your progress, equipment, and coins, there is a persistent currency called Fame Points which are spent to open up the game’s unlockable content. Fame Points are accumulated based on criteria like enemies and bosses slain in each excursion, as well as any optional quests completed. The quests, such as defeating a particular boss flawlessly, offer some nice variability between playthroughs. Though most are easy to accomplish, some provide a fun, unique challenge.

The chase of unlockables gives the game good pacing, as right near the time it begins to feel monotonous, a new character or game mode is likely within your reach. The 3 classes change the gameplay considerably, though the Knave is a bit too similar to the Knight for my liking. Besides the normal campaign, the game also offers an Advanced Mode (where players start at level 80) and a Boss Rush Mode. Both expand the replayability of Slayin, but the diminished or removed ability to stack weapons and buffs leave them feeling a bit flat compared to Normal Mode.

The game’s soundtrack is solid, but not deep. Matt Creamer of Retro City Rampage fame has crafted a fitting chiptune accompaniment, but the number of songs is pretty limited. It would have been nice if the music changed to fit the theme of each new realm to break up the repetitiveness. Stronger theme development for each new world in general would have been a nice touch. For example, early on there is a graveyard section featuring new zombie and ghost enemies, but it is the only area crafted so lovingly, and the ghosts and zombies later show up in unbefitting landscapes.

To experience all of Slayin’s content and master its steep difficulty ramp will take a considerable time investment. The $0.99 price tag is therefore very fair. The only in-app purchases are Fame Points, and if you’re paying real-life money to get out of the duty of just playing the game enough, you’re doing it wrong. At that price, it is a worthy edition to any iOS gaming collection, and one sure to leave you hungry to slay the fearsome Dragon awaiting the bravest adventurers.