I must admit, I didn't come here with the intention of playing more than a five or so minutes, but in fact, I stayed for at least an hour. I actually like this one and I think I'll check out Rot Purge as well. Might be a lot of fun!
Solid visual design. Voxel graphics usually suggest that the developer looks for simplistic graphics which are easy to pull off. This does not always yield a satisfactory result as developers don't always know the difference between nice, simplistic visuals and simply lacking visuals.
Fortunately, in this case, it can clearly be seen that actual work went into making sure the game looks pleasing while also using simple graphical solutions. Both the ingame graphics and the menus are rather nice.
Fun gameplay. The controls are simple and easy to remember and the player character responds well to the player input and these things can easily make or break a game. The first day/tutorial level gives a nice taste of what to expect and the game just escalates things from then on at a relatively okay speed. After saving up some money and getting a shotgun, the first possibilities arise to get a taste of the rampage mode, which gives a nice flow to the levels as more and more zombies appear on each day. The challenges are okay, while the harder level choices are clever and fun. I do like that the player has the choice to do a normal day to day level or the modified level at the start of each day.
The unlock system.
The game does not make it 100% clear how costume unlocks work. First, there is the coin collection system, (more on that later) and the shop. The game tells the player that the blue coins can be used to unlock costumes. To be honest, I did not reach the highest rank ingame as of the writing of this review, so there might be for purchase costumes later on that I do not know of yet. However, for a considerable portion of the game, costumes seem to be unlocked automatically when their rank requirements are met. This devalues the blue coins considerably, as they seem to be totally useless for quite a while. Weapon unlocks are totally okay on the other hand.
While I'm at it, I'd recommend an alternative to the unlock system; achievements as unlock conditions for unlockables, retro style. This is a much more fun way to go about unlocks IMO, as the dev is forced to come up with unique achievements and let's face it, achievement hunting, within the realm of actually doable achievements, is much more fun than endless grinding for a fixed amount of virtual currency.
The blue coins.
As far as I am aware, these things can be lost as a death penalty. Which, given the above point about them being effectively worthless for much of the game, is not the best way to go about such a feature. The rank system seems to work nicely and some form of an experience related death penalty would be much better in my opinion.
Back to the blue coins; my other problem with this system is that it reminds me (and I am probably not alone with this) of the dual currency systems used by many free-to-pay type games which plague the mobile gaming market. It is not a big deal here, as there is clearly no such scam in the game, but it does give off the impression that Rot Purge might include such shenanigans and that is not a good way to grow the potential player base.
Still, this might be just me being way too cynical for my own good. Take this as a word of advice, something to consider.
Some things could do with some polishing and reworking, but all in all, Rot is a fun little game and I will definitely take a look at Rot Purge.