I always assumed his size came from whatever black magic whatnot brought him back as a murder zombie, but look at this big bastard. https://3.bp.blogspot.com/-ereUGPjHB-I/V7ZJKfYDO1I/AAAAAAAA9so/pJCfYWvZypsurKVJnKRdbhA_OeRRu07PQCLcB/s1600/Sion_Splash_2.jpg If giants exist in this universe, he has to have some of it in his blood.
GreenLore5 votesI doubt that barbarian sion is actually his canon-appearance before death(we got a picture of how he looked and he had a different beard). However I think he was that big already in life.
Solari Fortune3 votesWell in the League Universe we can have Giant Space Dragons killed by a rat with a blow gun, so it not hard to believe Giants could exist
Serevas1 votesThis is an exceptionally good point.
DorkunedAuras2 votesSion was human. He was a big human, but not crazily big. The modifications that made him a zombie were... intense.
NJALobo1 votes[deleted]
Warlord Dienekes2 votesCalm down there Gragas, you know you fight better with your beer.
MavenSong1 votesI wouldnt have been surprised if they changed his body a bit during the Resurrection.
Ralanr1 votesGiant blooded individuals would make sense.
Though Giants may not be as giant as we would imagine in Runeterra. For a giant to mate with a human, the sizes need to be...compatible.
Giants could be ten feet tall (guessing) and it's entirely possible that they're extinct. Noxus could have conquered tribes of Giants in the past and used them as war machines and possibly experimental breeding for better warriors.
Sion be a result of a few generations after such an experiment.
Or he's just big.
