The king of strategy and diplomacy games. I'll start with the negative: the only, but significant, drawback is the length of a game, which can easily reach 1 to 2 hours per player, depending on how familiar they are. In the recommended player count of 6, it usually takes an average of 9-10 hours! This means you need to plan a whole day to play a game, so you'll need special permission from your partner, kids, family, etc.

HOWEVER - once you overcome the fact that it requires a whole dedicated day, we're talking about THE epic game. Beyond the strategy, expansion, research, conquest, and battles, which are all very interesting but would ultimately make it an overly complex and super deep Risk (and there are already such games, like Eclipse), the game has a whole diplomacy and negotiation mechanism that elevates it to the best experience you can have with a board game. For example, during the agenda phase, after hostilities or the round's conflicts, it's time for the galactic council, where laws can be voted on that favor or harm certain players, and everyone gets to vote on them, even those who are not interested or affected. Why?

Because everything is up for sale. Your votes in the agenda phase can favor someone who is weak militarily and desperately wants to ban large weapons. But it's not just there - throughout the round, you have an open dialogue with your fellow players. Are you the strongest militarily? Exploit it and force others to pay you to avoid the consequences. Want to occupy a planet? Make an agreement and "rent" it for a round. Do you have economic or research superiority? Extract favorable conditions from others for yourself.

So the game becomes a truly complex, competitive, and interactive game of diplomacy and dominance, where everyone tries to find a way to prevail, but in the next round, something might happen, the objectives that will be revealed might be different, or the two powerhouses might clash on the other side of the galaxy, and thus the balances are dynamic and constantly shifting. The better prepared or more flexible player can prevail, even if it doesn't seem like it now. That's where the game excels.

Along with this, I highly recommend the expansion, Prophecy of Kings, which adds things (exploration and artifacts, leaders for each faction, and an extra unit type), as well as fixes minor flaws in individual cards, which, for me, is now the only way to play TI4.

Summary: If you have the time and a group that can commit to it, it is the best gaming experience you can find.