Outland is a really cool idea and a really good game as well. It's a puzzle platformer where you can switch between red and blue, while you're red, you can jump on red platforms and blue bullets can hurt you, when you're blue, you can interact with blue objects and red bullets hurt you. You also can only damage enemies of the opposite color. These simple ideas, added to a metroidvania shell with a very neat artstyle combine to form such a thing as a 'bullet hell platformer' that plays well and should be tried.
I always try to play PC games with the keyboard and mouse, but I quickly had to change since there are so many keys to remember and it was way easier to do so with the simplified controls of a controller. You start with no abilities at all and you have to progressively pick them up - keeping the metroidvania spirit - as you go through the game. The ability to switch between "life" and "death" is one of the first big things this game does differently and it bases most of its puzzles upon that concept. A classic example would be to jump from platform to platform while switching dimensions in the air. Or climbing a ladder and switch at the right moments to block the bullets that rain upon you.
By defeating enemies and breaking pots, you get money that can be used to upgrade certain characteristics of your character, mainly health. You can also find hearts to refill your health and I enjoy the fact that if you're at maximum health you can break those for some money. Your health is quite precious since there is very little invulnerability between hits, that means that you might get hit multiple times by the same hazard if you're not careful, and that can be a bit frustrating. You also find other rewards from defeating enemies such as charges to power your special moves.
That said, the game is bad at rewarding you for completing certain optional side explorations, mainly because its reward is concept art. I really wish it would've given something more useful that ties to gameplay in some way, since concept art is pretty low in my list of rewarding things. You fight enemies by slashing your sword around, either in front of you or in upward/downward motions. It's a bit primitive and most enemies take multiple hits so you have to know when to get away before they hit back. Although it's also a bit random since I've managed to kill many enemies by just mashing attack in front of them, but some other times they would also get a hit in, even if I did nothing differently. Bosses also make an appearance in Outland and they are the usual platforming type of big foes with patterns and vulnerability periods when you have to hit them.
I didn't get very far in Outland anyways because of the checkpoint system, which is my biggest issue I had with the game in the time I've played it. Whenever you die, you get sent back to the last checkpoint you passed and you have to redo all the puzzles/platforming between now and then. A puzzle is okay once or twice, but not four times. I also lost progress twice by leaving a room (to get the 'Saving...' prompt) and then leaving the game, only to return at the beginning of the last room. It seems that the game isn't really saving your progress, so it's hard to know when you can safely quit. That made me stop after I got to the third world.
But you shouldn't let that bad part of my experience stop you, I can see the merits and the interesting parts of Outland even if my own time with it was soured by such technical - or perhaps design-related - issues. It's challenging, but it's plenty original and it handles fairly well, something required when the game asks so much of you.