A game where 100% of the content is created by its players will always have the same 3 problems
1. If the players can concieve of a meta, get the same items or can't get many new items very quickly, then your players will always be making the same "content"
2. You lose any potential for unique encounters and themes (look at a game like furi, where bosses are aesthetically and thematically similar).
3. Players are ♥♥♥♥
In my short experience. I encountered 20 bosses, 11 of which worked (didn't stand still, or become inaccessible) and of those 11, I beat 3. Yet I didn't really deserve to beat those 3 because the bosses were either poorly designed (for example, they had no abilities or because practically every boss had the SAME abilities). Mirador's bosses are all just dudes in armour, with the same selection of abilities just in different orders. When the crux of your game is customisation you need to demonstrate the maximum potential of the system you've created, like how little-big-planet has a dedicated campaign which aims to inspire and demonstrate what can be done with the tools in its creation mode. Otherwise, I'm just sitting in a sea of samey and uninspired community creations (half of which don't even work) and I have no motivation to seek out an actual well thought out boss.
So, knowing that one of the two key elements of this game are lacklustre by concept (not necessarily by design), what about the other one, what about combat?
Its OK.
Hitboxes are OK except for in some circumstances where dashing feels like it "drags" your hitbox behind you rather than carries it with you. Swinging your sword feels good, however I can't seem to pin down the exact amount of time you need to hold X down to get a heavy attack (It might vary based on what you were doing before you try to heavy attack). Shielding is annoying. Its powerful, but doesn't reward absolute precision as you need to start blocking very prematurely.
Its also rather flawed in that it doesn't reward aggression very well, give you any variation in playstyle or provide any character customisation / build system. You have a light attack, heavy attack, shield and a boomerang (which is just far too clunky in my opinion). And that's it.
Beyond that, a plethora of bugs and poor optimisation, I simply cannot recommend this game. It has the foundation of a good idea but when that good idea consists of ONE function of gameplay and ONE function of customisation then they have to be so perfectly polished. And due to the "player makes the game" nature of the idea, you're simply better off chasing the end of a rainbow.
