It could be a powerful Voltron commander, except for that power cap
As for Shadow itself, card draw is nice but the real draw here is the fact you can repeatedly drain each opponent of life whenever you trigger this ability
Wizards clearly stated back in 2016 that it has no desire to police proxies, even for in-store play, as long as the events aren't sanctioned and the events are using traditional proxies and not counterfeit cards
8 Knight of the White Orchid Ramp is something mono-white used to struggle with until we started getting more cards like Archeomancer's Map last year
Its card draw on a red-white card that also has a team-wide protection buff, and every little bit helps
Thats an outrageous bit of value attached to one of your characters and it also protects you against the classic one-two punch of the meta defining ruby-amethyst control deck of set two, which would wipe your board with Be Prepared and then answer the first character you play with a Lady Tremaine which would force you to sacrifice it