5/5.
I'd rate 4/5, but I want to encourage author to make sequel with cool combos(like bashing someone into wall and bouncing back, using corpse as a shield, super-high jump for getting onto ceiling and then bouncing back onto enemy you can't kill from side(ie.: he kicks you back), etc.)
GOD! First time I played I built stable tower out of 98 bricks, I said myself "Nah, don't worry about that piece, it's easy and you'll score the badge next time"
I'm now trying for something like ~9h(including yesterday) and I barely can get past 60 blocks!
AaaAAaAAAAaaAAAA