Of course, you don't /have/ to buy Dark Sun to play in the current round of Encounters, you just have to keep playing one of the pregens. (And people wonder why the pregens seem so sub-optimal?)
Actually, I haven't been too impressed with Dark Sun, so I didn't pick it up. But, I do like the (sub-optimal, but still kinda fun) Brawling Fighter pregen I'm playing, so I will finally get around to picking up MP2...
The point is, there's no requirement to buy to play Encounters. Just if you want to play a remotely optmized character.
OTOH, Gamma World Game Day wants to require you to buy boosters - like it was a magic tournament or something. I have a feeling that's not going to fly...
The local shop I've been going to for Encounters - Illusive Comics and Games - is fairly new to hosting games, and they had a sudden rush of players, from one or two tables up to four, when another store in the same county started chaging 3 bucks to play Encounters.
Three lousy bucks.
I'm a big fan of Gamma World, always have been since the first ed, and I'm afraid it's going to see another dismal performance, not because the game isn't cool, but because - once again - it's being hitched to another games wagon.
This is the 7th ed of Gamma World. The 6th used d20 Modern. The 5th Alternity. And the third MSH. All of those eds did /very/ badly. 1, 2 & 4, OTOH, were actually /just/ Gamma World, and did fine.