TL;DR
T3 Hover: the Goblin
T1 Walker: CS-Gunner
3 new weapons: RC-Large, Mini Jet, Rocket Booster
Goblin
The first T3 vehicle for the Dept. of Science. Officially designated with an acronym so long nobody bothers, the platform is better known as the Goblin.
Originally built as a mobile Rail Cannon carrier for long-range fire support, trials showed the chassis could survive closer work than expected. Later batches were up-armored and up-gunned, shifting the Goblin into a front-line heavy weapons role.
CS-Gunner
An attempt to preserve infantry effectiveness in the age of combined mech warfare.
The CS-Gunner has proven especially effective in urban incursions: small enough to weave through buildings while maintaining the firepower to deal with any soft targets within.
New Weapons
RC-Large: A Large T3 Rail Cannon. Rushed into service by the UEE. It prioritizes decisive shots over efficiency, user safety and long-term durability.
Mini Jet: Small sized down scaled Plasma Jet. Uses an emitter with reduced damage output, but while firing it produces the same forward thrust as the larger Plasma Jet.
Rocket Booster: A repurposed portable rocket used purely for thrust. Provides short bursts of acceleration instead of dealing damage. Most effective on light frames, though can be difficult to control.
Other
Updated the Hover vehicle icon to be more distinct