What a great game!
Despite some very minor issues (like the music track not matching the situation, or the shield animation confusingly stuck on top of the flower) I had an amazing time playing up to phase 4. It was very fun to get power-ups and new swords.
However, after that the pacing goes down, as the bosses progress quicker than me, requiring more and more time (despite me having 7 rarest swords). Phase 7 onwards turns the game into a clicker, where I would appreciate having some sort of auto-attack (especially considering that it is impossible to have any downtime with that many swords).
But the grounds are totally here for a great game if you are going to follow it up! Visual effects, the player controls, camera direction, music and sounds feel very polished.