I don't like them. I consider a character in a game to be a "Crutch character" when they can carry you through the early parts of a game with relative ease.

I've been playing Fire Emblem Warriors. I got the season pass, so I got the DLC characters. Azura is a crutch character, and she has killed any desire to play Fates. So, she's incredibly frail, only has okay strength, but has good speed, luck, and skill. She also has the longest attack animations overall. Her special is longer than some characters' dual specials. However, she has one saving grace; her Blessed Lance. It's the only personal weapon to start at 160 strength, rather than 30 or 80. She destroys the early parts of the story mode with the sheer damage her weapon does, and destroys the late game by doing effective damage versus monsters. She carried me through story mode, and I was not happy about it. After she stops one-shotting enemies, she is absolutely no fun to play. If you want a non-flying lance user, go for Oboro. She may not destroy the campaign mode, but at least I won't have to hear "You are the oceans grey waves" 30 billion times.