For details of each boss monster's stats in each boss position, please visit https://docs.google.com/spreadsheets/d/1xjrf5Vh0mU4PyLko6RnhCtI85q7bqS8uPhBRgtS7s3Y/edit?usp=sharing .

Since boss stats vary greatly by location, some bosses that are extremely difficult in some spots can be easy in others, and vice-versa. The following references are handy for determining whether your party is ready to handle these bosses:

EvilWall Damage and Cheese Potential (compiled by Antidale)

Kainazzo Wave Damage (compiled by ZoeVermilion)

D.Knight Dark Wave Damage (compiled by Inven, with additional credit to PsyMar and Simbu)

Valvalis Def/MDef (compiled by Inven)

Wyvern Speed and MegaNuke Damage (compiled by Inven)

See also: the list of Alt Gauntlet battles by location, if you have that flag enabled.