Dovescape + Displacer Kitten + Phyrexian Altar + Emeritus of Woe // Demonic Tutor

Dovescape

Displacer Kitten

Phyrexian Altar

Emeritus of Woe // Demonic Tutor

How it works

1. Cast a copy of the prepared spell by paying its mana cost.
2. When you cast that spell, Displacer Kitten and Dovescape trigger.
3. Resolve the Dovescape trigger, countering the prepared spell and creating a number of 1/1 flying Bird creature tokens equal to its mana value.
4. Resolve the Displacer Kitten trigger, blinking Emeritus of Woe // Demonic Tutor, which enters prepared.
5. Activate Phyrexian Altar by sacrificing a Bird token, adding one mana of any color.
6. Repeat step 5 until you have enough mana to cast the prepared spell.
7. Repeat.