MTG > Combos > Krark-Clan Ironworks +Myr Retriever +Foundry Inspector +Scrap Trawler +

Begin casting a spell. Proceed normally until you are allowed to activate mana abilities. Sacrifice Myr Retriever to KCI. Both Myr Retriever and Scrap Trawler’s abilities trigger here, but wait to go on the stack until a player would get priority. Sacrifice Scrap Trawler to KCI. Scrap Trawler’s ability triggers, but it will wait to go on the stack until a player would get priority. You can play using 3 of the 4 manas added each time gain one Generate any other mana you need to pay for the spell, and then pay for it to finish the casting process. It doesn’t matter that you’ve made excess mana with KCI. The three triggers will go on the stack at this point in the order of your choice. The trigger from Myr Retriever’s ability should target Scrap Trawler and the trigger from Scrap Trawler dying should target Myr Retriever. Scrap Trawler’s trigger from Myr Retriever dying is extra and can target a 1 or 0-CMC artifact card in your graveyard. (If you return a Mox Opal this way, you net +2 mana on each iteration of the loop.) Recast the returned cards and go to step 1.