Yu Yu Hakusho (CONTAINS SPOILERS)

Ok, so, ive been looking for this one song for a long long time now and noones ever been able to help sadly. Im sorry that im requesting as my first post, but ive been looking for this song forever. It’s during the Yu Yu Hakusho anime and the second movie, though the second movie has a different version of the song. As for the series, two big moments it plays is just before Kuwabara slices through the shadow beast thing in Sensui saga, RIGHT before ( HUGE SPOILER ) Yusuke dies. I believe that’s also the first time it plays. Another time it plays is while Yusuke is finding his reason for fighting during the fight with Yomi in the Makai tourny. During the second movie, a different version of it is played as Yusuke and everyone is using that massive spirit gun at the end that mimics everyones special attack.