I'm still afraid of Flandre and never went back since I cleared it.
If that stage only gave one more goddamn life....nope, only 3 default and 2 from stage, no matter how many points you get, you get NOTHING.
Dying with bombs even only once pretty much meant a failed attempt, I've usually entered QED with 2-3 bombs and always failed in the last 1/10.
Repeat 9 times before I've barely managed it with 1 bomb left.
And Patchouli. WTF. Hardest Extra midboss.
Silent Selene - 10/129
Royal Flare - 2/125(one was the MarisaA trick, another was complete luck)
Philosopher's Stone - 11/110
Mokou on the other hand was nice enough to throw you bombs and the stage gave you more lives.
It was the first Extra for me, finished it with the reach another spellcard - practice it - repeat way and it took around 30 attempts.
Same for Ran and Yukari, both took around 30 attempts. Suwako took only 16, only Koishi kind of makes me rage thanks to her WTF survival and Genetics.... Still, made it all the way to her final 2 times now, so she can't take 130+ attempts as Flandre did.
If only EoSD gave you one more life.....
Well, if you can defeat Flandre, you have no other Extra to fear IMO......except for Nue, I guess.