Though i also recommend starting with Lotus, this is the order in which i acquired power:
Ruby > Recall > Sapphire > Time Walk > Lotus > Emerald > Jet > tbc..... still missing Pearl and Twister.
If you got a good offer (like i did) you are good to buy other pieces of power before Lotus
Whenever you cast an instant or sorcery spell, create an X/X colorless Construct artifact creature token, where X is that spell's converted mana cost.
3UU, Exile Metallurgic Summonings: Return all instant and sorcery cards from your graveyard to your hand. Activate this ability only if you control six or more artifacts.
For me this card is vintage playable. In a big blue deck it should be really fast on the board and will give you an army of Constructs just for playing other spells. Draw two cards for zero Mana and get a 5/5? Sure
And if you don't need those pesky creatures anymore you can just get you're time walks and recalls back.
Congrats to Collecter and the rest of the Top 8.
As ChubbyRain (great work btw) mentioned i went 5-2 with Jeskai Mentor where both of my losses coming from white eldrazi and most of those games (1-4) weren't even close. Seems like the Eldrazi menace has finally arrived in Vintage.