From ZealotSG:
Scarab to Scarab is a fun trick conceived for Halo 3 Done Segmented. It’s nowhere near legendary, but it was really a blast! The goal was to launch from one Scarab to the other, achieving the fastest Scarab double kill possible. In a span of three weeks, I experimented with various approaches, documented in this HBO post. On August 22, I discovered a launch trajectory that would always take me to the Scarab. On August 24, I successfully accomplished the feat, documented in the video above.