Introduce a rating system (e.g. time spent to complete each level) and an objective (e.g. earn golden / silver / bronze stars depending on the time you need to complete the level) could add something to the game.
Game is great: it deserves a straight 5/5! As said by others, though, it is rather annoying to search for scarce resources on last upgrades, mostly pearls and chitin. Sometimes I ran short of others (solar cells, ozone, metan, aberrant matter, uranium, titanium) but in general it is much less frustrating to get these... For pearls in particular: there are no more than 3 oysters on each planet and they don't show up on minimap until your optics is upgraded to the max... I burnt most of my 50 planets searching for oysters!
@primeoverlord: I found the treasures in completely different locations than yours. Looks like you can find them wherever you dive: it is just a matter of diving.
Actually I found all the bossess pretty easy. Normally it is enough to stay still, and adjust your position a few pixels higher or lower in order to avoid each burst of bullets...
I love zombies (hrmm... let's say killing them) and I was tempted of giving a 5/5 but in the end the game is abit easy: just run at full gas, upgrade, tun at full gas, upgrade,... it doesn't look the upgrade order or driving ability matter much. Anyway still a satsifaction to see all those zombies splattered on my windshield :-)
This is a wonderful example of how you can make an addicting game even without high quality sound and graphics! If you get the right mix people will break their fingers on the mouse just to check which is the maximum limit :-)
Has anyone noticed that if you invest your money "wisely" you can obtain an auto damage higher the click damage, making it more convenient to idle than to wear your mouse? :-)
Am I the only one for which the game runs deadly slow? It is still playable, but in the first minigmame ("whack a crab" :-) I can't get enough points for the gold cup simply because the game is soooo slow that not enough crabs show up within the time, even if I got all of them right.
Don't know if the game was updated since previous comments, but my ending screen (as well as the starting screen) say clearly "get it FREE on the App Store". So there's nothing to buy and - yes - they let you know in advance... where is the problem?
Don't know if I am the only one, but I found relatively easy to finish all 15 standard levels while still can't complete challange at level 4. And 6, and 7... Isn't difficulty rather unbalanced on challanges?
Hmmm... nice game overall, though a lot of objects you can interact with are useless. One things did surprise me: final choice is completely senseless, as it leads you to the same final scene... which doesn't explain the reasons behind the murder!
Agree with most of the comments above (some lag, not so bad for me but maybe a quality toggle would help. Bullet speed as an upgrade is not a bad idea). Also, there is a disproportion between the game progress and the stars you earn: I finished all the levels at hard difficulty and played some of them twice, still I managed only to get the gatling completed but personal skills and ally are upgraded 3/12 or so... Why put the upgrades if you can't get them and they are not needed to finish the game?
I can't understand whether there is any sense in the number of stars assigned when you complete a level... does using more/less bombs matter? And destroyng more/less structures?
The game looks much more balanced than cyclomaniacs (at least for my skills ;-). Is it at all possible to "get first place in level 4 using Routemaster"? It seems to be the only acvhievement I can't get...
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 "Flappy Run"){kind=icon}
 "Glean 2 Preview"){kind=icon}
 "TF2 Crate Sim"){kind=icon}
 "Deep Sea Hunter 2"){kind=icon}
 "Earn to Die 2012: Part 2"){kind=icon}
 "Idle Mine"){kind=icon}
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 "Raven Crime"){kind=icon}
 "The Most Wanted Bandito 2"){kind=icon}
 "Collapse It 2"){kind=icon}
 "Flip and Go"){kind=icon}
 "Renegade Racing"){kind=icon}
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Ok! Edit: Updated!