Soldier vs Soldier The Unskilled Commander Ep. 127!

Match 3 of Commanders with CMC of 2:
Baird
vs
Soldiers
vs
Dina
vs
Myr

[SteelCityBrad]

With Scrap Trawler and Myr Retriever, each can get back the other. Since the cards enter the graveyard at the same time and THEN their abilities trigger, they are both in the graveyard when you have to declare your targets. Scrap Trawler's trigger can target Myr Retriever since Myr Retriever's mana value is less. And Myr Retriever can target any artifact, which Scrap Trawler is.

Fun fact, cards like these are the basis for Modern's infamous Krark-Clan Ironworks combo. KCI ultimately ended up banned in Modern, not because the combo was too good, but because it was too complicated. A lot players didn't really understand how it work and it caused lots of tournament problems & judge calls.