Uninterrupted combo line with Ostinato is as follows: Ostinato using 2 Refrain to summon Bacha. Bacha summon last Refrain from deck. Refrain add Couplet. Couplet revive a Refrain. Scale Couplet and activate effect to grab Concerto. Concerto to summon a 2nd Bacha using Couplet in scales + a Refrain on field. Refrain and Couplet re-scale. Refrain scale effect to dump remaining Couplet. Overlay both Bacha for Absolute. Use Absolute + the last Refrain on field to make IP. On resolution you activate Absolute to summon Vortex, Bacha to summon Refrain from GY, and Concerto to draw. Link IP and Refrain for Exceed. Exceed add back a Refrain. Exceed summon either Couplet from GY or Refrain from hand. Link summon Apo. You can then pend summon out 2 Refrain later for an XYZ play
You actually ritual summon Pendulumgraph (usually on the opponent's turn with Blessing). You just have to pop a scale with Tornado for the negate to be live. I opted not to Pend summon out Pendulumgraph because then it doesn't get the summon from extra
