What Skeletal Teror said is right...it starts to get boring around...level 25-29, but if you get lvl 30+ its fun...but then it gets boring...around level 40+ but its good if your bored!
Ok well, first of all my friend told me about it, and i decided to get it. it's really addictive at first, but I ended up getting bored, but if you're one of those types of people who are really into like, challenging games i suggest getting it. it's fun, but be warned, it tried to kill my computer with the 'slow bug' aha ^^