He has one too many skills-- the limit being 7.

1. Ancient Warrior: As an Ikanian, Ilgos is far, far older than most he'll ever meet in Hyrule, and has the combat experience to show for it. By fighting for thousands of years in a bloody civil war, he built up much experience in the art of war, making him nearly unmatched in single combat.

(According to the wiki, there would be nobody for Ilgos to engage in a bloody civil war with. Perhaps prior to their being cursed, but that's it. And the only Garo in Ikana Valley would be the ghosts that once belonged to the spies. The Garo would have no reason to pester the fallen kingdom of Ikana after they were cursed. The kingdom is fallen. Could you perhaps be more specific as well? Surely he favored a weapon after "trying them all out" and devoted his time and attention to mastery of that instead of mastery of everything. Although it would seem rather pointless to train so hard when your entire race has been cursed, your kingdom has fallen, and nobody really cares to bother the haunted place.)

2. Nobleman: Ikana promotes based on two things, and one of those is combat ability. By proving himself skilled even by Ikana's standards, he rose in rank and once again proves himself nearly unmatched in combat skill.

(Is this a talent or a title?)

3. Skeletal: While making him a bit more fragile, his skeletal nature also makes him more agile, giving him a better ability to avoid hits. He is still not as fragile as he appears, as he is held together fairly well by the curse.

(This seems kind of contradictory. So are you saying his bones are fragile and may break? Or that his bones are invincible because of the curse?)

4. Curse of Ikana: The Curse has proven to be both a curse and a boon. While it makes it more difficult for him to blend in (not that he really wants to) and marks him as abandoning the Goddesses (not that he really cares), it also grants him eternal life and a very slight talent in the dark arts of Majora, allowing him to have extremely limited shadow manipulation. This is really limited to darkening an area slightly to give him an edge in physical combat.

(Can you specifically lay out what the Shadow Magic does?)

8. Literacy: Ikana was many things, but primitive was not one of them. While Ilgos may not be familiar with the written Hylian dialect, it is similar enough to his native language that it wouldn't take long for him to learn.

(Could probably eliminate this one unless Ilgos reads a lot in his spare time rather than mastering weapons.)