Yeah needs lots of gold. I use 3* and 4* to power up 6*. The thing is I already got most of the heroes i needed at 6*+5. So i usually accumalate lots of 4* over time. So when a new good hero comes i can +5 him/her/it fast.
Depends who u already got and what is your focus on. TBH kris is really good and irritating with his zombie now. But rudy is always needed unless u already got a high level evan.

If you have Nia, one time jump all clone bye bye

My line up is

FY (Back)
Dellons, Lubu or Nia, Ace, Diao chan

Wave 1: Diao chan cast void shield to protect ACE > FY cast big sword chop
Wave 2: Dellon silence Shane and let her stand there kenak chop (Basically she won't move after silence due to slow attack speed), cast another void shield before kill her
Wave 3: Give all u got to kill Wukong and when he revive > Nia/Lubu debuff > give another all kill shot

Pass already without rubies retry but wasted 4 keys to retry la, haha..

Last one with full team member survive plus FULL HP bar

Line up:

Back liner - FY
Front - Dellons, Lubu, Diao Chan, Ace

AOE better. I use ming ming at the back. Usually i go, dellon silence, daisy reduce def, ming2 both skill and just whack away.

if backliner, of cos Crit/Crit

Use crit crit counter counter make your weapon +5 put him in the back and watch him kill everyone. if u have Eileen in team even level 40 heroes are like tofu to him.

Ada bagus sekali. Seriously. Good support unit with piercing and immunity. Even if he don't make your team, he is perfect for hard dungeon.