The other day I installed some gameplay mods, which had the extremely unintended side-effect of making the chosen spawn more than they usually do. Like a lot more. Like literally every mission for several months (doing the blacksite switched it back to normal, I think).
I would still take that over fighting the Berserker Queen with only this much prep work. No casualties is an A+ result.
Spoilers for SPICY STRATS below
I think some other people mentioned this, but since rulers get a reaction when you USE overwatch, not when it triggers, overwatch traps and ambushes are really effective. And of course things that let you squeeze more damage out of your turns like Rapid Fire, Chain Shot, Rupture, Banish, Deadeye, or hair triggers, is desirable.
What they don’t tell you about the frost bomb is that for rulers, freeze doesn’t tick down on the alien turn. Which means you can drastically reduce your risk by freezing them and then sticking to things that don’t trigger reactions, like shooting from outside their vision range with squadsight, arcing grenades over a wall, lightning hands, etc.
On the other hand, since status effects tick for every ruler reaction, damage from acid, poison, or fire tends to stack up HELLA fast.
Also, the berserker queen for some reason can’t just jump to higher elevation like faceless can, so she has trouble if you block all the ladders (or whatever). The AoE punch can still hit you, though, so it isn’t perfect.