The main cast

Background Information

Air Gear is a completed shonen manga series with 37 volumes created by Oh!Great (who is also the author/artist of Tenjou Tenge).

Minami "Ikki" Itsuki, is a student and a delinquent. Also known as the "Unbeatable Babyface", Ikki is the leader of the youth gang by the name of "East Side Gunz".

One day after getting his ass kicked by a gang of Storm Riders called the Skull Saders Ikki discovers a secret hidden from him by his adoptive family, the Noyamano sisters.

The sisters belong to a group of Storm Riders who go by the team name of Sleeping Forest. He steal a pair of Air Treks (abbreviated as "AT") from them and kicks some vengeful ass. In the process he receives more than the simple satisfaction of revenge, he gets to Fly (it gets Philosophical here). Determined to experience the sensation of flight for as long as he can, our headstrong protagonist is quickly sucked into the mysterious, yet irresistible world of Air Trek.

Standing in the Battledome

After some examinations and various upgrades for the verse, the power of the verse goes like this:

Pre-final battle Ikki and Sora are at least continent level+ to Moon level (both of them are superior to the Fake Sky Regalia Black Hole attack) and at least Moon level while using their full power.

What it was showed in the ''final'' battle was actually that neither of them had used the true power of their Regalia.

To elaborate more, before the battle, it was first shown in an hypothetical all out battle/simulation between Ikki and Sora, both of them at full power [most of the destruction was showed] could pretty much bring the human race into extinction in case they were using their Regalia's at full power = being technically life wipers, so, they didn't used them.

The upper high tiers like Rika and Ringo are likely continent level+. (Rika managed to fight for a while and execute some strong combo attacks against at least continent level+ to Moon level Ikki, and Ringo at her best is at her level, easily)

Kilik + rest of the Sleeping Forest members + Fake Sky Regalia combo = continent level+/Moon level = that powerful combo attack is part of the upper high tiers too.

also, the verse has many high tiers on the lower scale who are easily possibly around city level [like Nike, Kazu, Kilik, Aeon, Lind/Agito, Yoshitsune, Spitfire, etc], since the mecha with the A.T Railgun was a city level threat and was razing a large portion of a city in a short amount of time.

As for speed levels, the high tiers and top tiers are mach 186+ thanks to Yoshitsune.

So, the top tiers [like Ikki and Sora] of the verse can easily rival most of the high tiers/top tiers of the HST.