Throwback to Armistice from the original Envertol.

I wanted a one-drop white uncommon creature. I didn't have any set effect in mind, so I figured trying to homage mechanic from the plane's first use was a valid design. +1/+1 counter felt like the natural way to go. Because there could be times when that's backbreaking, I decided to let the opponent choose. I realize that white doesn't typically ramp, but I also don't expect the opponent to choose that often (unless the opponent is playing Getting Rusty), whereas tutoring a Plains to hand repeatedly can thin the deck too much.