You have to clear the level with the entire Toad Brigade, meaning you can't let any of them die or you won't clear the objective. Problem is the different parts of the level are so frenetic you have to find the way out while avoiding the enemies as well as keep running away from that dang Mummy-Me. I have lost so many times it's not even funny. Here's an example of the level and how it plays out:
Before I asked if someone would make a code that makes the Toad Brigade members invincible upon picking them up, since the other invincible codes for the game only work for Captain Toad/Toadette. Not to mention that there are other Toad Brigade levels where you die if one of the Brigade members are hit, even if you have an Invincible code.
Frankly I'd be happy with that, or an automatic objective code, or even a code that kills all on-screen enemies with the press of a button, now THAT would be a huge help!