Civilisation 6's Portugal is similar to Civilisation 5's Portugal, but with more restrictions. They can only have sea-trade routes, but get a free trade route slot every time they discover a new civ and make significantly more money from their trade routes. In the mid-game they can use their Nau (melee ships) to build Freitorias in friendly city states and civ's cities for more production and even more income. It could also be seen as a "fixed" Venice from Civilization 5 as it has limitations that push it towards being extremely tall and rich, but still has the ability to actually make new cities. Regardless, Portugal is an extremely unique and powerful civ to play as.
The Zombie mode added by this pack is also a pretty enjoyable experiment from Firaxis. The number of zombies can become overwhelming in the early game, but this also adds experimental new trap tiles that do damage and walls that deal damage and have zone of control. You can also use certain monuments to control hordes of zombies to throw at enemies.
Have not played this much, but it is an interesting novelty worth trying out.
izigame.me
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