Rex's new helmet is a mix of his old helmet and the newer Episode III-style clone helmet. His T-visor retains its Episode II proportions, requiring a lowering of the rounded chin pieces to fit. Rex's body armor is an upgrade to the Episode III version.
Blink and you'll miss them: Barriss Offee and Ahsoka Tano are part of the Umbaran campaign, and are briefly seen in the space battle during the opening narration in this episode.
The AT-RTs the clone troopers ride into battle on Umbara have the legion number "501" stenciled onto its side.
ARC Trooper Fives's helmet has a stylized Rishi eel painted on it, in tribute to the creature that attacked his unit on the Rishi moon during his very first assignment, in the episode "Rookies."
This episode introduces a new helmet type for the clone gunship pilots, which are very reminiscent of combat helicopter pilots in the modern military.
The gunship that Obi-Wan stands next to during the trooper briefing has a painted narglatch as its nose art. These hardy cat-like creatures were seen on Orto Plutonia in "Trespass."
