Question: How many and which episodes are Team Galactic in? I'm trying to watch them all, but I stopped liking Pokemon right when Diamond and Pearl ended.

Hey,I hope I can help wewe okay
The first episode where Team galactic is in is

A Secret Sphere of Influence!

This is the episode 504 from Diamond and Pearl.
(You just can see Saturn at the end)

The inayofuata episode is
Journey to the Unown
from Battle Dimension..Its episode 527
wewe can see saturn..and some members of team galactic trying to make something in ruins(just watch)

The inayofuata episode is
Enter Galactic
from Battle Dimension..Its the episode 536

then
Team Galactic Attacks! (1)
from Battle Dimension...It's episode 563 and I must say a real good one.with all the commanders and cyrus..

and then the sekunde part episode
Team Galactic Attacks! (2)

its the episode 564 and of course from battle dimension..

inayofuata episode is
Steeling Peace of Mind!
from Galactic battles..Its episode 578

then
Saving the World from Ruins!

the seecond part..its episode 579 and in Galactic Battles...

okay the there is episode
Gateway to Ruin!
from Galactic Battle and this is episode 604

The last episodes are the ending for Team Galactic..there is the trilogy between the episodes

Unlocking the Red Chain of Events (618 I think9

The Needs of the Three!" (619)
and

The Battle Finale of Legend (620)

* the numbers can differ from the german and the english and the others*

And i hope I could help a bit and sorry for my bad bad english because I'm German..xD