This is one of the stories that hold a deep place in my heart. I knew nothing about the Crimson Avenger before this since he's only mentioned very rarely in DC these days. In current continuity he's considered one of the first DC heroes to show up in the "modern day" inspiring the later Justice Society and Justice League.
Lord knows if it's still in continuity, I think it is, but he's fought alongside the Seven Soldier of Victory and while originally just a classy suit wearing character he later donned some superhero duds which kinda look silly but they do remind me of the Dan Garret Blue Beetle so I can't call them awful. After his stint with the Seven Soldiers of Victory he was transported to the near present roughly the time Infinity Inc started to show up I believe.
Still it's also a good example of a backup story being so much cooler than the front or main story and I hope you folks love it.
DC Comics Presents #38
Just under 2 and 2/3 pages from an 8 page story.( The Last Tale of El Vengadore Rojo-The Crimson Avenger! )