Alpha Blogg from Metroid Prime 2
You have to stand still while it charges at you so you can shoot it's mouth and then sidestep right away after shooting. Dashing at the right time can be really annoying because most of the time it either opens up it's mouth way too late, or just never opens it's mouth at all. Also, there is no given save point before the fight, so if you die, you gotta do all the stuff needed to unlock the area where it's at again.