Re: [AGI]SkyTerror ,The wyvern rider
Seems nice and something new. Reducing armor to 0 is very strong, but otherwise not overpowered. Just Harpoon will do for the name. Altitude sounds too un'warcraftish'.
4s AoE disable with damage. Overpowered. Either reduce the disable to 2s max or remove the damage. Ground targeting is too easy so the disable shouldn't be strong.
The ability itself is overpowered, and it's even more overpowered with a sub-skill that is strong enough as a normal ability. Flight, unobstructed vision, full evasion and increased speed. Then damage. It's still freaking overpowering even with the self-damage. That's like 5 or 6 effects in 1 ability. Too much. If you want suggestion, I'd remove the vision, evasion and sub skill. Harpoon is strong enough with flight and bonus ms. It's like Arcane Orb + target cannot escape from you. OD is jealous.
A side note on sub skill. I notice a lot of suggestors who like to flood their heroes with sub skills. I applaud them for being creative and having lots of ideas, but cramming everything in a hero is not really healthy, at least in a real dota hero's sense. A sub skill should not do anything more than a simple trigger of something based on it's host skill. Detonate, Jaunt, Reality are some examples of what real and practical sub-skills should be. They are very, very simple.
Casting spells without costing mana is overpowering, especially if your hero already has such decent INT gain. You can try to balance it by making his INT base and growth the worse of all heroes though. I'm serious. There's also no duration stated? You can try to combined the sub skill to this charge-based concept but maybe you want to scrap the free mana part. He's not a mage.
Overall a pretty overpowering hero right now, with overpowered abilities, strong range and stats. I'd like to see Wyvern as a hero though. Still need tweakings and perhaps some skill changes. Hope my review helped.