I think its the base for an awesome game
The mechanics are fun, and there are alot of neat card combos to use, but having no control over your deck kinda hurts it. I love that someone has made a flash card game, and i think you have the base system down for quite a good one :) My only problems are with how training seems to do nothing(I've only played 20-25 total games, but none of my stats have increased at all), and how there is no control on the cards in your deck.
The main thing that really increases my drive to replace cards in my deck is that there are sooo many cards that are just superior versions of other cards. Like i wish the card that does nothing but cure poison was either deleted or made so it did something else, since theres another card that does the same thing, but heals you one as well. The sameapplies for the lower level healing and damage cards. Maybe the different 1-3 damage cards could do a side effect, like punch could make your enemy take 2 damage plus be unable to heal for 1 turn, or the quick slash could do 1 damage and give you 3 hazumi. Things like that would make alot of cards not seem worthless, which kinda detracts from the fun when you draw a card like "heals 1 point" instead of something like "gain 1 hazumi every turn" or an 11 damage or such.
Basically though, your game rocks, and i hope there are future versions with either some sort of customization, or with more varied cards. Even if my deck was never modifiable, the weaker cards having secondary effects like a 1 damage +1 defence attack just seems really cool. Wonderful job though :)