Game is really really laggy, and has no sound on Firefox. You need to debug this or at least warn players who might use browsers lacking HTML 5 support.
I can't beat this latest level. (3rd before the final Christmas stage). Everytime I get the computer down it has a combo (usually white hole or some other horrible spell) and kills me. The computer shouldn't just get whatever card will beat your hand automatically...
In Giant Lans, 'Sirin' should be spelled 'Siren'. And I encountered a glitch where the game freezes after I went to Giant Land and entered the Watch Tower on hard mode.
Hopefully badges for "10 is Again" will be here soon! :)