While there are a ton of powerful and challenging enemies in Clair Obscur: Expedition 33, many of the endgame and secret bosses take the cake when it comes to difficulty. If you struggled against the likes of Sirene, Visages, or any of the other main story bosses, those encounters pale in comparison to some of the Act 3 side bosses that you'll face if you travel into the far reaches of the Continent. Luckily, even the toughest enemies can be overcome if you put all the different weapons, Pictos, and Luminas to good use.