The Protojet is on the left, and the Air Lancer is on the right.
In the show Tenkai Knights, one of the powers that Guren, Ceylan, Chooki, and Toxsa learn is called Robofusion. This ability combines the four into a powerful jet aircraft to battle enemies. They have unlocked 2 separate robofusions: The Protojet and the Air Lancer.
The Protojet is a white, blue, and red jet and the first robofusion that the boys unlock. It is a delta shaped jet that has Bravenwolf's sword acting as the nose cone. The Protojet's most prominent attack is the Phoenix Attack, which transforms the jet into a phoenix that can destroy things simply by ramming into them.
This jet first appeared early in the first season. The boys use this jet to attack Granox's headquarters. They then try to battle Vilius with the Protojet, but Vilius robofuses with his soldiers to form the Xenoship to defeat them.
The Protojet isn't seen again until much later, where it is seen battling the Sickle Ship that was created when Granox and Slyger robofused with some Corrupted soldiers. The Protojet used its Phoenix Attack while the Sickle Ship used its Dark Raven Attack. The Protojet ended up winning.
At the very end of the first season, Guren, Ceylan, Chooki, Toxsa, and Gen gain Phoenix Mode from the Tenkai Dragon. They then use the Protojet robofusion to reach the Sanctuary of the Guardians and then use their Phoenix Mode powers to stabilize the malfunctioning portal. The Protojet is seen at the start of the second season, where it is used to battle Vilius' forces after Vilius suppressed the boys' Titan Modes. The Protojet defeats most of the soldiers, but Vilius defeats it with the Xenoship.
The Protojet can be built irl by combing the extra parts from the Bravenwolf, Tributon, Kutor, and Leinad figure packs.
The Air Lancer is a yellow, green, and gray jet. It has Lydendor's boosters as its tail fin, and Valorn's staff as its nose cone. The Air Lancer's most prominent attack is the Tenkai Thunder Cannon, which shoots lightning from the tip of the nose cone.
The Air Lancer was first used in Valley of Secrets. The boys try to execute Robofusion with more than four people(including Beaq and some of his men) and end up creating the Protojet and a new jet: the Air Lancer.
The Air Lancer isn't seen again until the final battle of the first season. The boys robofuse into the Air Lancer and use the Tenkai Thunder Cannon to bust a hole in Vilius' fortress and then fly the Air Lancer into the hole in order to infiltrate the fortress.
Protojet And Air Lancer - Tenkai Knights/Ionix