I guess this is a good game, but an explanation of how to play would help. Even if the explanation was only "stand still untill the enemy impales itself on the pointy thing pointed at them"

Fantastic 8bit stlye dungeoncrawler! The gameplay was a blast for me, very unique and fun, trying to find the perfect timing and place to backstab your enemy without him or the others seeing you. There's a good mix of tactic and skill involved.
Also, that soundtrack got me really pumped and excited to defeat 'em all! ;D

Great game! I remember when I played chat foncé by you, that was another awesome hit with a minimalistic style like this one! :^)

So I like the concept i.e. you have a blade "thirsty" and wanting to "slay" all your enemies. That said you don't have gameplay explained very well in the game. After trying the game again here's some tips for those whom would like to play it (updated the rating a bit higher from what it was in light of giving it another try).

A few positives I'll note is that I like that you get powerups automatically when you kill enemies i.e. you don't have to run over them to pick them up. A nice touch that makes the game a wee bit easier. Also you're rewarded for noticing when an enemy is aggresive or running away in that you can get some cheap kills if you're paying attention.
Finally there's no time limit which also helps. That said it would be nice if, in later levels, you did have a time limit that gets more restrictive as you go along. Can't keep the kid gloves on forever, right?

Anyway...STRATS!
1. What you want to do in combat is to 'poke' your opponents by hitting them, retreating briefly so they don't hit you, go towards them just enough to hit them, rinse and repeat. Don't tank the enemies that's gonna get you killed fast. Play like you're Morrigan or Magneto...not Haggar or Hulk (Ultimate MvC3 reference).
2. Sword powerup raises attack speed (I think). Heart with a cross is life regen. Shoes increase speed. The potion one seems to slow enemies' attack speed.
3. After each level you can raise a stat once. Raising attack is probably your best bet at first since you need to kill enemies in as few hits as you can. A little extra HP early on is not gonna save you but extra damage will. Defense might be good too since you literally go from 0 to 1.

Due to giving the game a revisit, and talking to the author a bit, I like the game a little bit more. Still not a great game by any means but with some improvements it has potential to be good. Like a more simplistic version of Gauntlet.

My main suggestions would be naming the powerups (a word underneath one when you get it, or the word flashing on screen briefly, would be ideal). At least the first time you get it. After that you should know what the powerup is from memory. Then again figuring out what they do is a tad bit fun.