What ship was used as a defensive ship then offensive one.... That is smaller...

12 minutes ago, shark1j said:

What ship was used as a defensive ship then offensive one.... That is smaller...

In EU, new canon, or Armada?

I think in new canon they only have raiders, dreadnoughts ("Imperial Support Vessel" I believe they are called now), and Arquittens, out of which I imagine the defence roles would fall to Raiders or dreadnoughts.

In EU, I think Carracks and Lancers were defensive, Lancers as anti-squadron specifically/only, Carracks as anti-ship.

In Armada, I dunno. . . Raiders?

I think this question is pretty much impossible to answer based on movie Cannon because the Empire almost exclusively* uses ISDs and SSDs.

Consider:

Episode III - very end - we see some Venators guarding the Death Star under construction. *This is the one exception I'm aware of where the Empire didn't use an ISD or SSD.

Rogue One - both Death Star and Scarif are defended by ISD-I

Episode IV - Need to rewatch to confirm, but I don't recall seeing any capital ships guarding the Death Star

Episode V - SSD and ISD-II used when attacking Hoth

Episode VI - SSD and ISD-II used to attack (defend against?) Rebel fleet at Endor

Star Wars as a franchise isn't really known for using effective, let alone reasonable, military strategy. There is actually a really interesting US Navy War College thesis comparing Star Wars to the MCRN from the Expanse on how to ineffectually squash a resistance (use massive slow ships like ISDs) vs effectively (use loads of small fast ships like Corvette-class Frigates and Morigan-class Frigates) as applied to USN force structures and compositions.

I digress.

What would make sense to me would be ISD /SSD for defense with **** tons of TIEs and a combination of Interdictor / ISD / Carrier / Arquitens / Gozanti for offense. Kittens and Gozers scout, Carrier provides extra TIEs, ISD provides heavy firepower. Interdictor stops you from escaping.