This Ice Age enchantment dominated competitive play in the mid 90s, since it turned your life total into a nonstop card advantage engine
A 4/4 for two isn't terrifically impressive in this day and age, but back in 2012, it neutralized a Tarmogoyf well on two axes at a time when Modern was defined by the Lhurgoyf
I've already mentioned Gisela, Blade of GoldnightGisela, Blade of Goldnight, Elesh Norn, Grand CenobiteElesh Norn, Grand Cenobite, God-Eternal OketraGod-Eternal Oketra, and Avacyn, Angel of HopeAvacyn, Angel of Hope, but that is far from the end of the list
If you are an aggressive and sneaky strategist, Emerald and Ruby is for you
Mark Rosewater spent some time answering questions in the wake of this