Aliens Speaking English: The White Star meets the Drakh, making First Contact between the two races. After Lennier sends them language files, they begin transmitting a message in Minbari. Only one problem: Lennier sent them language files in Interlac, not Minbari, which reveals that they have met the Minbari before.
Continuity Nod: The Mars Resistance has not forgotten the time that Captain Sheridan served with the task force that put down the Food Riots during the show's Back Story.
Do a Barrel Roll: "Skin Dancing", which involves smaller ships flying as close to a larger enemy ship as possible to avoid taking fire. The White Stars do this while accelerating so they can pick up enough speed to escape before they can be shot down.
Enemy Mine: Sheridan is teaming up with the Mars Resistance. The last time he and they had anything to do with each other, it was on opposing sides during the Food Riots.
Loophole Abuse: The Warrior Caste have driven the Religious Caste from several of the southernmost cities on Minbar. Many of the Religious died from exposure before reaching shelter. Minbari do not kill Minbari, but apparently driving them out into the snow where they'll probably die is okay, because it's not you doing the killing, is it?
Delenn: Is [Drakh] your name, or the name of your species? Drakh: Yes.
The Remnant: The Drakh, one of the Shadows' allied races, who are now apparently trying to take over as the main force of darkness.
Spot The Thread: Doctor Franklin delivers multiple messages from Captain Sheridan. One of these messages being an order to cease attacks on civilians. Afterwards, Number One points out that given the blockade and communications blackout (which had been mentioned repeatedly recently), there's actually no way Sheridan could know any such attacks had happened.