Is that the Lateralus music video?

In response I play counter spell

Nice!

Anticausal vestige for 6, then bounce off for U to put it back in my hand. This triggers a draw, followed by a zero cost chomping mastasaur. Discard the vestige, dealing 6 direct damage. Draw 1. Wild ride for R on mastasaur for +3/+0 haste. Attack with mastasaur, triggering a second discard (this time a second mastasaur) and a third draw, bringing the total to 12 direct damage before mastasaur’s attack, and 21 damage if you’re not blocking.

Kupo!

Edit: just remembered that vestige brings your free cast in tapped. Wild ride wasted and the total damage done is 6.

Oops.