When you look into blue, you find a lot of great cards, that return lands to your hand, most of which are generally useful to some degree
It's a big driver for building community
The artwork is beautiful, but the card's features are what really increases its value
For example, at the time of writing, a copy of Kindly Customer from Avatar: The Last Airbender has a market price of 24 cents, which an LGS may price around 50 cents to make a profit
Bonehoard Dracosaur Theres an old comparison between Mulldrifters, creatures with weak combat stats but valuable abilities, and Baneslayers, which offer basically no advantage outside of being giant battlecruiser creatures in combat