Combo
The combo is just two cards: a pili-pala controlled since your upkeep (not summoning sick) and a grand architect. This gives infinite mana of any color.
Combo goes: 1) tap 1 blue make pili-pala a blue creature 2) tap pili-pala to make 2 colorless mana 3) use the colorless to untap pili-pala and put a mana of any color in your pool 4) return to step 1)...
Infinite mana... now what?
Mindshrieker is a goofy little creature that insta-kills with infinite mana. It can buff itself too which is useful if the combo isn't showing up.
Spawnsire of ulamog lets you cast emrakul, eldrazi conscription, and ulamog from your SB for the win. You can chord for the spawnsire, or use Duskwatch recruiters ability to cycle through your entire deck til you hit the spawnsire.
Eternal witness + cryptic command lets you draw your entire deck by repeatedly returning e-witness to your hand and drawing a card, then recasting e-witness to pull back the cryptic. Add an aether vial on 3 and this becomes instant speed, letting you counter everything your opponent does from there on out.
Increasing speed and reducing variability
Chord of calling acts as pili or architect 5-8 (whichever you need) and is fueled by wall of roots. It can also act as a win-con by grabbing the spawnsire.
Collected company is actually worth it here... I usually hate this card, but its capable of hitting the main combo pieces (pili+architect) and some outlets for the infinite mana (duskwatch+mindshrieker), so it just feels right. Also hits e-witness or at its worst (above a total miss) can hit wall of roots or spellskite
