Rush does not work, how to rush?

Hello,

I was looking multiple tips and how-to(s) how to rush, and I am doing:

CharA - lower level
CharB - higher level which will rush CharA

CharA creates normal game in Act4, CharB joins the game and both are in party. CharB kills the Diablo while CharA stay in town (also tried stay next to CharB). CharA expecting to get Diablo quest completed and get to Act5 but instead CharA sees 'You can not complete this quest in this game. You can complete it by creating a new game."

What I am doing wrong? Thank you.

CharA needs to be within 2 screens of Diablo when he dies

Oh, thank you, that is exactly happened when CharA tried to kill D but then CharB killed it and CharA got the quest.

Then I have a question why in Youtube all are saying they rushee can stay at town and can get a quest?

As long as one person completes the quest, the others can stay in town.

In your example, CharA could have stayed in town if a friend CharC (who hasn't completed the quest either) was within 2 screens of Diablo when he died.