Tl;dr don't believe the reviews, the gameplay is satisfying and addictive. The controls are 100% responsive and easy to pull off. Unlike Megaman this game wants you to go very fast and kill everything.
You can dash, air dash, and low dash. Best part? Not limited to a single air dash and can keep doing it, although you lose altitude quickly. Also you can change directions and grab a ledge if you feel you're going to miss a jump.
I'm about 4 bosses in and the powers are pretty fun and have some utility to them. Near as I can tell there is kind of a weakness chain but not really. It's all about finding the right weapon to satisfy the conditions.
I.e. If there's a lot of small things at once use the Pyro form, if there's an enemy at an awkward angle use Dyna form. Etc.
You'll find yourself switching forms frequently.
The difficulty comes from 3 places.
Your Xcelerate(the dash kill), hazards, and tough bosses.
Lemme explain the risk of Xcelerating. You hit an enemy X number of times, they flash a color, then you dash into them. The faster you do it the more Xel (points and [parasitic bomb]) you get as well as boosts in power, speed, and I think defense. However there are a lot of times there are many enemies placed at once or a really precarious situation so you can't dash all Willy nilly. You have to be careful and fast. That's where the excitement and frustration. You wanna go fast but you need to pay attention because this game is NOT shy about 1 hit deaths. Hell, a boss has one. (very avoidable though)
The music feels very Megaman 1 (swear I hear part of Firemans theme in the boss tune..) and the sounds are great although the voices and SFX drown the music out! You can turn those down and its much better. You can also adjust your controls to your liking. I set Dash to the ZL (left bumper) because of the Zero/Zx series and it feels a lot better.
Graphics are good for an indie game and a Wii U title but nothing worth mentioning really.
This game is all about the gameplay and it feels great.
I bought it on the Wii U shop for $20 and picked up the DLC for an additional $5.
Definitely worth it. Haven't touched the DLC yet.
+Fun as hell
+Tough but fair
+Feels fresh with some Megaman vibes
+Multiple air dashes (!)
+Good visual design and characters
+controls are flawless
+Great price
+Music never feels out of place or too subdued
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-Lazy storytelling
-Bad story
-No facial animations
-So-so English voice acting at best
-Stages aren't very difficult or interesting in places
-Very long load times even for just respawning!!!
It's a very good game just don't go in expecting Megaman 11 or whatever. Playing it like a Megaman game will [tornado fang] you hard!!