Teshar triggers, returning Scrap Trawler from your graveyard to the battlefield.
Activate Lion's Eye Diamond by discarding your hand and sacrificing it.
Activate Yahenni by sacrificing Scrap Trawler.
When Scrap Trawler dies, it triggers, returning Lion's Eye Diamond from your graveyard to your hand.
Resolve the Yahenni ability.
Repeat.
This intricate recycling loop lets you generate infinite colored mana, death triggers, and storm count by constantly feeding the machine. At its core, Teshar, Ancestor's Apostle acts as the engine, turning every historic spell cast into a resurrection tool for low-cost creatures like Scrap Trawler. While Lion's Eye Diamond provides the necessary mana injection right from the graveyard, it forces you to empty your hand as the cost of doing business. Meanwhile, Yahenni, Undying Partisan serves as the willing executioner, safely sacrificing the returned artifacts to keep the death triggers and Scrap Trawler recoveries flowing indefinitely.