It's fantastic, but...c'mon..it's incredibly easy. Once you get the perk of having killed enemies repairs your castle, and then fireball upgrades, it's easy pickins from then on out considering it was even hard from the beginning. There was maybe one time I got a bit worried as to how hard it was going to get how fast, and that lightning and fireball alone weren't going to cut it, but that was quickly diminished.
The graphics aren't something horribly impressive, but in this case I don't feel it matters, as the gameplay is so much fun it can carry the game by itself.
However the game certainly needs a difficulty tune up, or more levels and maybe skip giving a perk or skill every couple levels. Or just give more levels, but have the perks become...hmm..not to beneficial to your goal, or maybe good, but with some kind of downfall. Maybe a boss or more difficult enemies, whatever the case it's fun..and makes you want more, but short and easy. I guess in essence it could be great for teaching about other perk and skill type games, a short tutorial-ish type thing to show things will be good, some will be great but have downfalls...i dunno.