User blog comment:BannedLagiacrus/Discussion of the Week: Final Bosses/@comment-24734669-20160507134311/@comment-4969421-20160507154136

Glavenus' tail attacks have big hitboxes mainly because its tail is huge, but that doesn't mean you can't evade/bushidodge/block/move out of the way/whatever them. Glavenus tends to leave itself open after a tail attack as well. The spinning tail slash it does when enraged has the widest hitbox out of them all, but you can evade through it without specific armor skills or styles. The fireballs are trickier as they explode after a short while, but you can always simply move out of the way to not get hit, while also keeping an eye on Glavenus.