I like the idea so much, idk if it's original but it is good.
anyway, this game needs a lot of things, like more upgrades or mechanics.
idk if it's me but the sword is pointless, because of it's very short range, i would like a spear instead, or like a dash-like ability.
Very good game and recommended.
PD: i don't understand the "stat" thing, like mushrooms upgrades, i really don't know what changes, or don't feel it, neither the attack speed, don't seem like a useful thing in my opinion