Was Articuno this difficult during its original week?
In my first Articuno (and first legendary) raid, there were only 6 of us, and we beat it. It was quite a fight, but we did it. I participated in three more before the ice bird went away and beat them all. I recall it never being an easy fight, but it was certainly easier than Lugia.
Fast forward to today, when I encountered the Articuno from Hell. There were 11 of us, and almost all of us lost our first team and had to go back in. At least 9 of these folks were ones I have raided with before. So we knew what we were doing. But OMG. That thing was firing an ice beam every second, which was a OHKO for whatever was in its path. We did manage to beat it (barely) and, sadly, I didn't catch it. But wow! Was I just lucky before and never encountered an ice beam attacker? I distinctly remember a blizzard, and it wasn't like this.
Answers
Lugia only has a single weakness to rock and Golem only resists one of Lugia's attacks, so IMO there are not the same benefits to reward using Golem given the risk of Hydro Pump.
My lineup for Lugia has shifted to include 2 Tyranitar (B/St and B/C), 2 Gyarados (B/H and B/C), Dragonite (Dt/O), and Lapras (F/B). I might shift a little if I know the moveset before the fight begins. If I think I might not make it with my first team, I back out after the two Tyranitars go down, max revive, and reselect as fast as possible.
