The Combo: Enduring Renewal Shield Sphere Ashnod's Altar The thought is to have an Ashnod's Altar in play, have creature with zero in casting cost in your hand (etc Shield Sphere), draw a Enduring Renewal. Play Enduring Renewal then play Sheild Sphere. Sacrifice Sheild Sphere and get 2 mana and sheild sphere jumps up to your hand. Repeat this and you get infinite mana. Add-on to the combo could be Fecundity to draw alot of cards (Fireball, Stroke) and kill to opponent. Replenish would fit with some Bazaar of Bazaar of Baghdad, Attunement and/or a Frantic Search.