This expansion offers very late-game features. This is very catered to those who get this to the table very often and need more ways to change things up. This primarily changes up the base-game components, such as the player board, and the core module tiles (such as treatment rooms and gardens, but double-sized).
IMO the price doesn't live up to the value you get out of this (unless you play this game a lot).
Speaking purely from game design, this is a great expansion to replace portions of the base game with, since the base game tended to gear most optimal builds towards egg-laying. Oceania nerfs this and promotes spending of resources (spending on nectar for points and playing more birds in general). It makes it easier to play high-cost birds, which means a good chunk of cards are more usable.
Mage Knight Board Game: Shades of Tezla Expansion
Its thickness feels somewhere between Sleeve King penny sleeves (soft, flimsy and easily scratched), and a premium sleeve of any brand (notable thick, stiffer, holds a flat shape).
These are a high-gloss surface, but are pliable enough to look like a higher quality penny sleeve than Sleeve Kings penny sleeves (possibly also Mayday- I've no experience with them). These would be excellent for archiving and you require high clarity, but if you don't like the idea of playing with cards still in packaging bags, get some other premium sleeve instead (such as Gamegenic Prime or Dragon Shield).
A diverse set of factions to play all with their own strengths and weaknesses This is one of my favourite board games of all time and fully recommend this to anyone to play and this is a great start to get into it with differing factions included to fight against each other. Along with the needed dice and board to play.