Oh my lord:
Final Fantasy 10
Out the butt. The theme for Suteki Da Ne, which I would say serves as the thematic material that outlines the relationship between Tidus and Yuna which is paramount to their success on the journey, is re-used and rehashed in quite a lot of pieces, although in rather beautiful ways.
(skip 42 seconds in)
(Starts the first 10 seconds or so)
Leitmotif (variation) 2 (Go to 30 seconds)
Risk of Rain is another good one, though the leitmotif in this one is more simplistic in nature (4 notes):
Risk of Rain Track 1 9Main Thematic Material comes in in the first 10 seconds.0
Risk of Rain Track 2 (Main Theme comes in again around the 25 second mark. A few pitches are changed, but the same overarching theme is there. (Now that I listen, I am hearing a LOT of Ed Harrison influence in this, haha))
He does a lot of alternating a few notes, though you can still pinpoint the note series.
Calum Bowen's Super Ubie Land:
Main ThemeLeiter 1Leitmotifs are almost expected nowadays in any type of music media. If you want, I'd also suggest listening to Tristan and Isolde. Richard Wagner is one of earliest composers to be widely recognized for his leitmotif usage.