and can u explain me what is G rush plz ?
Glitch rush.
Rusher + bumper rush through the game as normal, and then all the leechers who are low levels that aren't high enough level to get ancients quest completed are able to bypass the restriction of not being level 20/40/60 for the ancients quests.
The leechers stay in town while the rusher and bumper go complete ancients and then baal in each difficulty and due to how quest completions are shared in the party, the low levels are given credit for the baal quest when they shouldn't be able to get it.