Free-to-play games often look appealing, but it's difficult to know at a glance whether the business model is insidious and fun ruining, or reasonable and worth pumping a few bucks into. With Freemium Field Test, we'll take a recent free-to-play iOS game, put it through its paces, and let you know if it's really worth your time (and money).

Angry Birds Space showed that Rovio could do more than simply dress up its tried-and-true series formula with new visual themes, altering the pull-and-fling design in an inspired, entertaining fashion. Sadly, the creative well ran dry shortly after that, and many of the games released since have seemed like half-hearted and desperate attempts to ride the coattails of surging genres.

Kart racer Angry Birds Go took such a hard turn into freemium shenanigans that it ruined any potential fun, Angry Birds Epic charted a head-scratching detour into fantasy role-playing, and Angry Birds Stella Pop was an obvious bubble-popping clone that tried nothing new. And now you can add Angry Birds Fight--a match-three puzzler lacking smarts and lasting appeal--to the increasingly sad pile. 

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The pitch 

As the title implies, Angry Birds Fight sees the familiar birds and pigs battling it out--only these fights are handled by matching together nearby bird faces on a grid. Pairing three of a kind clears the tiles from your board and adds a small bit of power and defense to your abilities, while matching four or even five faces triggers a special move that can generate a grid-emptying string of combos.

Sadly, there isn't much time to plot out maneuvers: Each round lasts just 45 seconds or less, which means you're expected to find matches at a rapid pace. Taking your time to set up intentional combos isn't really compatible with the game design in Fight. Not that the game really lets you make up your own mind without distraction: It's constantly suggesting next matches on the board without giving you a beat to consider the options. Speed matters much more than strategy here. 

That isn't a problem on its own, so much--there's nothing wrong with taking a different angle on a tried-and-true genre design. The real issue I have with Angry Birds Fight is that it all feels like a total crapshoot. Once you finish the puzzling segment, the opposing creatures start pummeling each other automatically--you'll do nothing but watch in these moments--until one of them is defeated. And it's not very clear what's happening: This a stats-based showdown in which the stats aren't all made known, and you can't do anything but await the conclusion. 

And Angry Birds Fight sure likes to match you up against higher-level players who will crush you with ease, with your quick puzzle-swiping performance playing what feels like a very small role in the outcome. No doubt, that makes the in-app purchases a lot more appealing, as they're the surest way to have a fighting chance in combat. 

The catch

Gems are the primary and premium currency here, and they are unbelievably expensive. I can't remember the last time I was so taken aback by the lacking value of an in-app purchase once I knew what it got you.

Angry Birds Fight awards a gem here or there as you progress through the various missions and boss battles, and collecting five of them lets you have a pull of the slot machine. The typical gear you earn from defeating opponents is rarely all that beneficial, but the stuff you get from the slot machine is often amazingly powerful or protective, giving you a big leg up in battle. But the free gems come very slowly, and players willing to open their wallets wide can pay for a big advantage. 

And I do mean wide: A pack of five gems--just five--costs $4. You'll pay four American dollars to play a digital slot game once and earn a random accessory for your cartoon bird warrior. Pricier gem bundles offer some small level of savings, but not much: 10 gems costs $7, a 30 pack is $18, and it goes all the way up to 140 gems for $75. Angry Birds Fight says you're saving 46-percent over the single gem price of $1 in the largest bundle, but those gems do not go far no matter how you stack it.

I snagged the 10-pack to gain a couple of extra slot machine pulls, and sure enough, the gear I won easily outclassed whatever I'd been using before. There's an obvious benefit to spending money in Angry Birds Fight, but little in the way of resulting satisfaction. The puzzle gameplay is shortchanged by the emphasis on speed and inability to think out moves, while the battles feel meaningless and randomly decided. Yes, you will win more if you pay to use the slot machine, but why bother?

Rovio likes to stack freemium elements, so it's little surprise that Fight has not one, but two different energy systems. The birds' energy bar loses one of six notches after each fight, while your ship--used for occasional monster battles, which have the same kind of pairing of puzzling and watching--has its own three-part meter.

Play for a decent stretch of time and Angry Birds Fight will start asking for gems to refill your meters--otherwise, you wait. Fight also lets you watch video ads to earn a mysterious stat boost in battle, in case the game wasn't freemium enough for you.

The verdict

Angry Birds Fight has Rovio's trademark production values, with a great-looking tweak on the usual bird designs along with amusing character interactions. But it's window dressing on a game that doesn't deserve the attention, as it misreads the appeal of the match-three genre and loses the plot with its empty battles.

Fight is fun in the early moments: It's cute and fast-paced, which makes it ideal for short sessions in your commute or other slow moments. But everything else feels poorly conceived, not to mention designed primarily to push you toward in-app purchases. Rovio used to be a mobile leader, but now it just chases trends--and often badly, at that. Angry Birds Fight is only the latest proof of that.