Look, I was as cynical as anyone. "Take down forts, castles and even a fire-breathing dragon in Catapult King - the King of castle crushers!" goes the iTunes blurb for this latest Chillingo offering. Yes, we've gone full circle. Crush the Castle begat Angry Birds and now the games that are jumping on the Angry Birds bandwagon are starting to look like Crush the Castle again.
The title alone pretty much spells out what you'll be doing. Pull back the catapult, aim and release, and try to use your limited shots to knock down structures, killing all the enemies in the process.
Are there different shot types? Of course. Standard rock-and-twine balls are good for demolishing wooden structures, but do minimal damage to those that are reinforced or made from stone. Metal cannonballs will plough through stone and wood alike. Is there one that detonates like a bomb? Naturally. And there's even one that splits into three, offering a wider damage spread at the cost of lower impact. All have their Angry Bird analogues, and all work exactly as you expect. This is not a game of surprises.
There are even equivalents of the Angry Birds Eagle, in the shape of earthquake and meteor storm power-ups that can be called upon. These come at the cost of your magic points, but will help demolish a tricky level.
Where Catapult King is concerned, the difference is largely visual. It's a full 3D polygon world, and you view it from a first-person view, over the top of your catapult. This may seem like a semantic change, but where this sort of game is concerned, it's actually fundamental to the appeal.
As Christian recently pointed out, sometimes the fun of a game comes from the mechanics, the innate appeal of playing with virtual physics to see what happens. That playfulness is at the core of the fling-things genre. One of the first games we learn to play is knocking over stacks of blocks. It's why most people can't be in a room with a snooker table without absent-mindedly whacking the balls off the cushions, just for fun. That's the itch that Angry Birds scratches, which is why most players seem not to care about the opaque scoring.
Catapult King has similarly opaque scoring, with bronze, silver and gold crowns for each level, augmented with various combinations of gems depending on how many enemies you got in one shot, how much damage you caused and so on. What Catapult King also has is a much more visceral, and much more satisfying, physics model. Sending a ball thundering through a tower, making it slowly crumble onto wooden frames below in an avalanche of stone and splinters, simply feels better in 3D, as the camera follows each shot into the carnage.
In-app purchases sour the mood slightly, offering magic top-ups or all levels unlocked, but at least it never feels like the game is forcing you into situations where you're compelled to keep spending. The levels are cleverly designed - many feature cunning domino-like sequences that can knock everything down with one well-placed shot - but all can be beaten without the need to part with extra money. It comes close, on occasion, but you can always replay earlier levels to earn the magic needed.
So Catapult King is as derivative as they come, a proven formula presented with more whizz and bang. That bugs me, but it didn't stop me being glued to the bloody thing for the best part of a week. For all its low ambition, it's devilishly addictive and enormously fun. Every time a grumble about some borrowed feature started to form in my mind, it was drowned out by the elation of a particularly spectacular and cathartic shot. Catapult King doesn't quite earn the throne, but it's a welcome addition to the court all the same.
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