Kassandra is amazing and the game is great, but it's to big and not as sophisticated as Origins, when it comes to worldbuilding.
Odyssey reuses assets too often (caves look always the same for example), it all looks samey after a while and Athens isn't as epic as i hoped it would be.
Loved the loot and the RPG aspect of the game, working out your best build and trying out different armors and weapons, or upgrade your ship etc.., is all superfun and well implemented, also because the economy is well balanced (you always need money for something). You can make look Kassandra as you like (armor and weapondesign are varied and topnotch) and make powerful builds by upgrading and combine the right things.
The combat is good, but not the best. Abilities are very fun and powerful, but the combat relies too much on those in the sense that normal attacks are only here to fill up your yellow bars and than unleash OP abilities like hero strike again and again. Also there are no shields. Ulimately i enjoyed the raw simplicity of Origins' combat a bit more. I really enjoyed the fight against the mythical beast though, like the minotaur for instance. Well done!
The writing can be solid and is often pretty funny, thanks to some good characters and the great main protagonist. Questdesign is not a strong point of the game, since it is the typical Ubisoft thing. Don't expect big surprises on that front.
Odyssey is a fun game, but it's too big and the worldbuilding isn't that what i hoped for after playing the fantastic world of Origins. The RPG elements are ace in Odyssey!
