how the hell does grouping work?

[identity]

First time I grouped, some guy needed help with act 2 boss. I was like 48 at the time i think, so it was pretty easy.
Second time I grouped, it was a party of 3 on the same boss, they invited me, and now it's ridiculously hard that the other 3 aren't doing any damage pretty much.
I guess the encounters get harder with more people in the party, that would make sense, but this seemed like it was my level AND that much harder (because 4 person group)... when it was their instance in the first place... I don't get it.

[Parismio]

Yes. The more players are in a party together, the tougher the enemies become as well as better loot so its more incentive to play with other people. Its pretty cool. I was able to beat the Act 1 final boss with at least 3 players and it was tough, but we got through it. I joined a 6 player team I think for the same boss and hoo-boi was it much tougher and the boss killed us multiple times before we got him. I love it.

[DirtyMick]

They probably had level scaling turned on. There's an option that will make it so you go down to their level, so they can still get experience. This makes it harder to just get power leveled by someone, cuz if they turn it off, they don't get the experience from you just killing everything.

But yes, enemies are stronger with more people. Generally, it's still easier to play in a group, but if you have a really strong build and you're playing with 3 people who have bad builds and dont contribute much, it's gonna feel harder.