The altean Lance theory is a good idea for the whole Romeo and Juliet appeal but there are a lot of holes in the theory.
In season 4 you see this scene
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Hunk says "Alteans don't get brain freeze." But lance got brain freeze.
Next there is no way that lance could be altean because all the alteans were wiped out over thousands of years ago there are only 3 full alteans alive and 1 half altean.
Now you may say lance naming of his family members in season 5 not naming his father but his parents could easily be divorced. The divorce rate in Cuba is 64% that's a lot more than average,
Omg and the fact he was able to pilot the blue lion without Allura's help in Ep1 that is easily debunked. All of them were able to fly their lions on their own and keith was the one to find blue in the first place. It's not like the original blue paladin was altean. The lions choose their owners by personality not blood we learn this in the first episode.
Let's keep this "theory" to an AU only please. Good idea just not a lot of evidence.
And if you think about it wouldn't you see more signs of him being altean by now? We are almost to season 6 and there isn't much.
Future me: Season 8 Explanation
I was right but what happened in season 8 was allura put herself in lance (?) so he isn't Altean he just has the marks
