Large Transport (X) Models with the Large Transport (X) special rule follow all the rules for Transports, with the exception that they may transport Walkers, Infantry and models with the Bulky special rule. Each Walker model counts as two models for the purposes of determining how many models can Embark upon a Transport. In addition, Infantry models with the Bulky special rule take up one space within a Large Transport, not two.
Drop Pod Drop Pods are transports designed to deliver troops from orbit directly into the heart of the enemy line. A model with the Drop Pod special rule can and must Deep Strike, as described in the Deep Strike special rule. Models with the Drop Pod special rule can Deep Strike from the first round of the battle onwards, instead of the second.
Once deployed on the battlefield, models with the Drop Pod special rule do not need to maintain Detachment Coherency with other models in the Detachment, nor do models within the same Detachment need to maintain Coherency with Drop Pod models. In addition, Drop Pod models are ignored for the purposes of calculating a Formation's Break Point.
Many Detachments with the Drop Pod special rule also have the Transport (X) special rule. If another Detachment is loaded into the Transport Detachment during deployment, that Detachment is kept in Reserve alongside the Transport. When the Transport Detachment is set up via Deep Strike, the transported Detachment then immediately Disembarks and can then be activated as normal later in the phase.