Myriad Landscape is a nice way to ramp in a deck that doesnt have access to better methods, and it can pair well with Valakut if you already have five Mountains on the field
My guess, based on reading from online sources, books like A Collectors History of Magic The Gathering, and vintage magazines like Duelist, is that there were probably around 200 million revised cards printed
They are intended to make playing with the new cards more fun by clearing up the common misconceptions and confusion inevitably caused by new mechanics and interactions
The formats exploding popularity had forced players and designers alike to reconsider what kind of game Magic was meant to be, how and where it was played, and which mechanics were seen as relevant and valuable
Your friend is correct, he can prevent Wither and/or Infect damage just like regular damage
Each player needs their own deck of Lorcana cards, and using a starter deck is the easiest option if its your first game