Cross takes place a number of years after Trigger (I believe 20, but I dont remember), but they arent totally connected (what I mean is, it isnt a direct sequel and you dont have to play Trigger to understand Cross).

- The small part of the world that Cross takes place in isnt in the original Trigger, but was created by their actions from what I understand
- The Masamune and Doreen (Or rather, the Grandlion and Dream) play a small part, mainly in a weapon for Serge.
-A character in Cross, Glenn, is named after Glenn (SPOILER)Frog from Trigger.
-(SPOILER)You can find Epoch in the basement of Viper Manor
-Belthasar is around.
-You can visit a version of 'The End of Time' and fight Slash, Flea, and Ozzy
-Guardia is mentioned a few times