Original and fun.
Died once at level 3 - thought I had to kill the boss using chains (like the elves) - once at level 5, twice on level 7, maybe 5 times on level 8, got 191s (33.5k) on survival.
The chaining of normal items has really turned the game around. distanced it from the shooters it could previously be easily compared to and helped it become a unique blend of a chain-reaction game with a shooter.
I felt that by starting off with both directions, you missed a trick - introducing enemies from the left was a cool twist to witness in the original game and helped add variety within levels.
When I killed the boss, it felt odd for the level to just carry on - maybe if it continued - with a time bonus for time remaining - it'd feel more ike an occasion.
Speaking of occasions and celebrations, I was a bit disappointed at the lack of any ending animation after the king.
And I still think you should slow the pace a bit, zoom out, but make each hit take off maybe 1/3 of our energy. And make Fuzzy Elf's expression change.
The controls also started to feel a bit cramped - personally, I'd prefer the option to use a and w.
The new rocks were a cool addition and really encouraged me to stay alert. I also liked the way that the king now bounced around and needed to be avoided.
The chaining added aleatory elements but there was still skill involved.
The medal system could have been explained a bit - I assume it's based on life left, but am not sure. If I'm right, maybe it could have changed colour from blue to bronze to silver to gold as the bar 'measures itself' at the end of each stage - changing colour as it passes each threshold? And pop up the relevant medal at that same time?
Its existence means that when I return to this, I'll have another goal to play for.
A fun game you've got here and I think you should return to the concept sometime, with a few tweaks and maybe a couple of twists.
I'm only criticising it so much because it has potential.