You might not have heard of it, but Tencent's third-person shooter WeFire is a huge deal in China.
And now, Glu Mobile - a seasoned developer in all things shooty with the likes of Frontline Commando, Deer Hunter, and, er, Kim Kardashian Hollywood - has given it a few tweaks for the west.
Is it the next big thing, or is its appeal lost in translation? We'll be putting Rival Fire through its paces over the next seven days to find out.First impressions
If you've played a shooting game on mobile before, you'll be largely familiar with how Rival Fire works.
Playing to the limitations of the platform, you use one thumb to aim and another to fire. You pop out of cover automatically when shooting, and can run between cover by tapping arrows at the left and right of the screen.
It's a simple control scheme that works intuitively, and feels a lot more sensible than trying to recreate Call of Duty on iPhone - even if it does somewhat limit its long-term and competitive appeal.
Think of it like the CSR Racing 2 of the shooting genre - the gameplay itself is fun enough, but the real meat is in the upgrading of your gear.
Having said this, there's been a valiant effort to make the short, simplistic bursts of shooting gameplay more enjoyable.
There's a relatively chunky campaign, frantic PvP that pits you in a tense stand-off against another player, and a high score-based survival mode.
But it was the game's co-op campaign mode and guild play that really fuelled WeFire's success in China, and it's this upon which Rival Fire will live or die.
We'll dive in and report back in a few days.Day 5 - From strength to strength
The more you put into Rival Fire, the more it proves itself to be greater than the sum of its parts.
Campaign missions, while still necessarily confined to the shooting gallery formula, introduce a modicum of tactical scope with varying enemy unit types - medics, snipers, mission-ending bombers - that each require a different approach.
The environments are mixed up, too, from terrorist-targeted stations strewn with panicked civilians to the top of a speeding train.
What's been most impressive, however, is the 2v2 PvP mode, which provides as much minute-to-minute satisfaction as any online FPS - proving that it's getting the basics right, not mechanical complexity, that makes a good competitive experience.
With just some cover to move between, a player-controlled teammate, and some explosive barrels, these four-person face-offs are edgy affairs that reward both quick reflexes and shrewd teamwork.
Rival Fire is keen for you to learn all this before you get into dedicated guild and co-op play, gating its social features for much longer than many of its competitors.
But this feels like a positive. Now, as I join a guild, I feel equipped with the skills to be an important member rather than a passenger.
Let's see how that unfolds in a couple of days, as we see out the week.Day 7 - Squadding up
Unlocking co-op mode has been the icing on the cake.
It's not perfect, but the feeling of going into war alongside three other players - be they friends or strangers - is one that's rarely been executed this well on mobile.
The co-op action can feel overly hectic at times, and players aren't quite as sharing with the revivals as you'd hope, but it's otherwise a surprisingly smooth experience.
In this sense, then, it rounds off what is one of the most solid free to play shooters on mobile.
I care little for the Frontline Commando series, or the shooter genre in general, but there's a combination of simplicity and slickness here that's kept dragging me back.
Even if you're turned off by the beards-and-bullets aesthetic of Rival Fire, it's deserving of your time - even if only for the fast, skill-based, and fierce PvP.How are you getting on with the game? You can tell us and the rest of the PG community about your experiences by leaving a comment in the box below. Click here to learn about our free-to-play review policy.