It doesnt just triple the mana you make with your Lands, as any of your mana rocks also tap for additional mana, too
All Will Be One was no exception, whether you look at the characters, the Phyrexian story, or the cards themselves
Though maybe a touch too much mana for an aggressive white deck to muster in Standard, Halvar can do a lot of work in Commander in equipment decks
Additionally, the Reddit thread says that stores such as Barnes and Noble, Dollar General and Dollar Tree sell the cards
He cant win the game quickly by himself, but hes a three mana splashable Planeswalker who provides guaranteed card advantage
This powerful card hugely helps you develop your board by bringing out Characters at a low DON