A new format has been announced for Magic Arena!
The "news forge" is burning hot in Magic!
Say hello to Explorer!
"Explorer is a Constructed, non-rotating, "true-to-tabletop" format using all the Pioneer-legal cards available on MTG Arena."
"It will begin with the same ban list as Pioneer, but we may need to manage it separately"
According to Wizards, "one day Explorer will be "retired" as a format, and we simply call it . . . Pioneer"
"[...]supporting Pioneer on MTG Arena will take several years to accomplish. "All the cards that matter" means we'll be working toward all of the cards that are regularly played in Pioneer decks"
In other words, Pioneer is still far from being on Arena, but Explorer is a first, solid step!