Assuming he's not counting Kid Quantum, I think it's the first Legionnaire killed in the Mask Man story.
I want to say.... Ultra Boy?
The Mask Man story (from Adv 310) is what I was thinking of, and Ultra Boy is the first victim, even as the team still mourns Lightning Lad. Followed by... well... everyone else.
EDE gets next question!
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Yeah, I was taking a wild swing with that one. This is (I think) an issue that I don't own (if I do, its buried deep), but DO know exactly to whom you are referring. Unfortunately, the only reference I can find for the answer has an obscured scan, so I don't know what the word says other than "Lad"
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I actually had a really hard time viewing that picture, as the first half of the word is a bit fuzzy, at least to me. But I thought I read that as Estimate, but then I couldn't remember hearing about him, ever.
So then I did a search for "Estimate Lad" and found that he had been introduced in the Legion of Substitute Heroes Secret Origins.
So there we go.
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