Ok, I have put a lot of time, effort, and some money into this game.
Overall at this point I must say that I would not recommend this game.
Basically when you first start playing the game it captures your interest quite well. Being based on the Marvel characters and universe was enough to do that for me. Upgrading your roster and characters from star level 1 to star level 2 is challenging but enjoyable as you can easily see the improvements. So you get a nice feeling of progression.
Unfortunately once you start to move past star level 2 characters into star level 3 and 4 characters things start to go bad.
Upgrading your roster and characters from star level 2 to star level 3 becomes a nightmare because you first have to upgrade them 50% before they start to become useable. The playing time alone to gather the required resources to upgrade one star level 3 character 50% could take you a month. Throw in the fact that there is no scaling or bracketing in this game and players that already have full power star level 3 characters will sap points and rank from anyone below them and you start to get an idea of just how difficult a task this is.
For arguements sake, if you were going to spend 'real money' to upgrade a star level 3 character 50% instead of just playing the game it would cost you about US$100+. If you were going to buy all the powers for one character and max them out completely it would cost about US$400-US$600. So really, I would assume most people are inclined to play the game to gather the required resources instead.
Note that everything costs more as you progress. Characters from each star level catagory; ie: 1, 2, 3, and then 4 have an increase in 'experience' levels, hit points, damage per gem, and super power damage levels by almost double. But coming with that is an almost doubling of resources and costs involved for said characters.
This all adds up to the fact that the time you invest in the game has to increase as well. Where you might have been able to do well putting two hours a day into the game you will then have to put in three and then four hours a day. This doesn't mean all in one sitting just total overall time played per day. There maybe up to three events running simultaneously and if you wanted to do well in all of them you can sink alot of your time into it. You may feel obliged to do this since events are usually put into 'Seasons' and you may not see an specific event again until the next season or two in the future. 'Seasons' typically seem to run for the length of a month.
It's kind of awkward how events are setup. Each event usually lasts for 2 days or if longer are broken down into 'stages'. These longer events of up to a week are broken into 'stages' that last for 2 days each. What happens is to earn 'points' and keep you 'rank' up compared to everyone else, you have to play the 'stages' over and over as many times as 'plausible' in that 2 day period. 'Plausible' in that there is a 'full points' refresh timer of around 2.5 hours and also there is a point-catch-up (rubberbanding) system where the longer you wait between replaying the 'stage' the more points you can get. Also, each time you replay a 'stage' the difficulty and level of the enemy characters increase.
There are players that gain rank #1 and play the game every 2.5 hours even throughout the night. That is the type of competition you will be up against.
Ok, I want to end this review now as I think I have given you an insight into what is involved if you wanted to build and progress a roster of characters in this game. Or, what to expect once you have moved on from establishing a foundation.
A few other things that are really off putting:
A) Characters have been changed by the developers out of the blue. Usually termed as 'nerf' where characters are weakened or resulting in less useable. How annoying for those players that have spent time/resources building said characters up. You can sell characters, but you will only get a pittance of what you have put into them.
B) There have been a myriad of server issues over the time I have played this game. Sometimes this has had a catastrophic effect on the scores/ranks etc of whatever event was running at the time. Sometimes the developers have given out a form of compensation but not always. Two recent events had server glitches that cost me ranking high. Unfotunately they happen in the later half of the week long events when you have alreadly invested alot of time.
C) The free-for-all pvp system means that those with maxed out or high level characters can just stomp over everyone below them. How frustrating to come out of winning a battle for 20 points reward to be greeted by a message that you have been attacked by half a dozen players twice your level losing 200 points. They really need to incorporate some form of scalability or player bracketing to make play balanced.
I would recommend avoiding this game unless you are happy to invest all your free time into it.