This had the makings of a passable game, but was unfortunately marred by bugs that should have been caught and fixed prior to release. The art style is nice and the battle mechanics are decent enough when they actually work. The masks were a cute idea, and it would have been nice if there were a few that could be unlocked somehow. Perhaps as an alternative use for orbs after purchasing the other upgrades, for example.
However as many have mentioned, the dash command often causes the player to freeze, forcing them to wait until the boss kills them before restarting. Upon pausing the game, the boss was still able to attack (and kill) me with his lightning attack. When initially playing the game, after I purchased the 3rd weapon (I believe it was the Stone Sword?) it still appeared in the shop instead of giving me the option for the final sword. I clicked it once and lost an additional 100 orbs, and it wasn't until I reloaded the game entirely that the Shiny Blade became available. One time after I defeated the boss's first form, instead of dying he continued to attack me and his health bar refilled (I received the "Stage 1 Full HP" medal, so I know I killed him. Not sure if the medal is what caused the glitch). After killing him a second time he went immediately into his third and final form, completely bypassing the second form.
The following aren't outright bugs, but rather things to consider for any future projects. Without the Double Jump ability it's impossible to harm the boss's second form. However, you don't really need to jump much if at all with his first form, so to myself (and I'm sure many other players) the double jump upgrade seemed somewhat pointless, causing me to favor health or a stronger weapon instead. Because of this, once I reached the second form I was forced to stand there and wait for him to kill me so I could go back, get the upgrade, and fight through the first form again. If you're going to make a boss or enemy that requires a certain upgrade, try to consider ways to encourage the player to get said upgrade beforehand? Perhaps by giving the boss an attack that's difficult to dodge with a single jump but would be easy to dodge with a double jump, for example. I also noticed that from the first screen with the treasure chest the player can easily pause the game, open the shop, and click "play game" to "reload" the screen and open the chest again, getting more orbs without actually having to do anything. After a certain point I actually started doing this to farm orbs and get my final upgrade instead of fighting the boss directly. This might have been an intended feature, and to be fair the chest often has few obs in it, but it's always good to try and look out for possible exploits such as this to prevent the game from becoming easier than you intended it to be.
I also noticed that there was a Speed stat listed, but I never found an upgrade (that I noticed, at least) that ever altered the stat. Was this a feature of some sort that was scrapped before the game was released, or am I just missing/overlooking something?