This feels like a very spicy inclusion.
- For 2 mana lets you cast Hypergensis/Restore balance/Living end/Ancestral visions from the yard
- For 3 mana lets you cast Ancestral/Bolt and Ponder/Preordain/Ancestral Visions. Combos well with Filtering cards like Faithless looting.
- For 4 mana lets you timewalk and something else
- Triggers Phoenixes at any mana cost as long as you cast 2 spells with it