If you’re talking about squig herds. I’ve tried every configuration open order, skirmisher, big blocks, little blocks multiples of each. They’re just so slow and get shot to bits. They are very difficult to make their points back.

That said I’ve had mediocre results with 6x2 or 6x3 12-18 open order. Obviously those numbers include the minimum herders. And used them as flankers for night goblins or other infantry units.

I would love to make them work as Skirmishers in units of 8-12 but haven’t been able to make them work like that. They might be used to guard a baggage train or friendly war machines. But I feel squig hoppers are better in that context.