Their visual novelty was seen as a big plus, and the fact that one card had two different spells on it, each with their own name, was seen as exciting new mechanical space
He doesn't do much more than draw you a card and do Blood Artist-y things
However, you must also consider that this card could be banned sometime within the next year -- especially if its ramp causes broken synergy and/or combos with cards yet to be printed
Elephant Grass I dont remember if I was introduced to [casthaven]Elephant Grass[/casthaven] in my friends [casthaven]Gaddock Teeg[/casthaven] deck or his Bant Enchantress deck, but from the moment I first dropped this card, I was in love
Piloted by Charles Eiler, Selesnya Tokens won the SCG standard 10k on January 5, which explains the sudden surge of interest
Its also seen a spike in power level in recent years, as Wizards prints more and more cards to benefit reds impulsive draw mechanic, which lets them cast spells from exile until end of turn