Shito! Kyofu no kokushiken - S1-E11
Audio problem: Hyoga butts in with "What did you say you just saw, Ikki?", but Ikki was THINKING that phrase about seeing the battle, not saying it out loud - unless he was practicing ventriloquism without an audience. (00:21:50)
Shito! Kyofu no kokushiken - S1-E11
Other mistake: When Hyoga taunts Ikki at the end of the episode, Ikki's armor is miscolored, missing the orange sections on the breastplate. (00:22:05)
Shito! Kyofu no kokushiken - S1-E11
Plot hole: Changes made in the anime only make nonsensical the mechanics of the fight against Black Pegasus. The villain focuses on dealing one big hit to the side of the hero at the cost of his life, but that big hit happens just in the anime and has no consequence or purpose at all. Seiya collapses later with various black spots from the hits of the first barrage, the one that he thought gave him no damage and went instead under the armor, just like in the manga. Black Pegasus had already dealt his death blow by that time, and what he does in the anime in addition to that has no consequence or meaning.