Best Red Card: Etali, Primal Conqueror Etali, Primal Conqueror is technically a Gruul creature with green identity, too, but considering that you need red mana to cast it face up, I am listing it as my favourite red card
What if Empty the Pits just becomes the new Sphinxs Revelation
Large creatures with evasion and undying are very powerful and yes this card is expensive and you'll need lots of mana to capitalize on it, but it represents some of the more powerful things you can do in Magic
Even still, the ability to swap any artifact token (be it Treasure, Blood, Clue or Map) for a Blightsteel Colossus, Sundering Titan or Inkwell Leviathan on turn two means that the Welder is still a tremendously powerful one-mana Goblin
If youre building a white deck, you might also be interested in reading our article on the best white card draw in Commander