by yaverot
I did buy both at the same time, I played the base game about 2 times, then I opened the expansion and traded out the pawns.Then I played about another 4 times, then added the roles.
Since I've only used other expansion features twice. I've also been building my overall game library.
I also knew that if I didn't like the game, getting rid of it with the expansion would be easier than without. And since Pandemic wasn't available at my stores at the time, but Amazon had both, I also had the above "what if Brink goes OoP?"
I actually don't like the added setup complexity of the added special cards. So they sit unused.
But the question is getting both at the same time for you...
Is the game fun without the expansion, or is the expansion necessary to have fun?
I'd say the expansion isn't necessary.
If both are there on you shelf, will you get you full value from the base game, or will you dig into the expansion too soon?
Will you burnout on the game too fast and then not get the full value of the expansion?
Is the expansion going to become hard to obtain if you delay?
No, I think.
If you dislike the game, how/when will you get rid of it?
Trashcan, garage sale, last will and testament, local used store, Goodwill, game group, or math trade. Some markets are better with a complete (all expansion) offer, others just the base game is fine.
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Either way, base or with expansion, is unlike to be the "wrong" choice.
As my first co-op, I've soloed it a few times, in some ways solo is better because I'm not waiting for anyone, nor are they waiting for me. I can add additional tracking data to the board that looks like busywork to others. On the other hand, I want to play with other people, so I'd hardly call solo a superior experience - I have plenty of computer games for that.