Early on before the mission starts, Chopper gives a series of beeps similar in cadence to the famous "I've got a bad feeling about this" line.
The Infiltrator Droid is modeled after an early design of C-3PO by Ralph McQuarrie. This design has previously been used for several background droids in Rebels, identified as 'RQ Protocol droids'.
'Warhead' and the next installment, 'Trials of the Darksaber' were originally conceived as one episode. During a story pitch in July 2015, the events depicted in Warhead were to be the B-story while those from 'Trials of the Darksaber' would have received more time as the the A-story. Another version teamed Zeb with Rex instead of Chopper and AP-5.
Hobbie and Wedge have non-speaking roles at the start. Wedge is wearing a n A-Wing helmet with the name "Mala" written on the side in Aurebesh. This is a reference to Wedge's girlfriend Mala, who died on the Corellian moon Gus Talon in a Legends era short comic book story titled "Lucky", published by Dark Horse in "Star Wars Tales 23" (2005).
The Aurebesh word that is almost constantly visible on the Infiltrator Droid's view screen translates to "scanning". At the beginning, the words "possible target acquired" appear, and when the droid is scanning Zeb, two phrases pop up, that translate to "non-bosco face" and "species: Lasat".