Sapphire cards offer players a more strategic style of play, with more cards that have abilities affecting the gameplay through discards, revivals, and card buffs
Smothering Tithe in particular plays very nicely with this card, letting you draw a card on each players turn in a Commander game
Players will want to take advantage of all the various forms of removal in the Emerald and Ruby starter deck, from returning Characters to a players hand through Cruella de Vil, Miserable as Usual, and Action cards like Dragon Fire
It becomes a lot more difficult to win with Thassas Oracle if your graveyard gets shuffled back into your library and Underworld Breach wont do much if your opponent doesnt have a graveyard
AddIronheart, Clever Champion to the mix, and those artifacts gain Improvise, too, letting you use them for paying mana costs