Reading through the core rulebook, it says that one Handler and all of its Minions are roughly a match for 2-3 guardsmen. However, it doesn't seem to specify how many Minions each Handler is supposed to have in order to be at that power level. Minions vary wildly in power, too, so it's really hard for a newbie like myself to gauge how many one should have. Is there a good rule of thumb for this, or is there otherwise an official ruling somewhere that I've missed? In particular, I'm interested in Gretchin, Snotlings, and Squigs since the group I'm GMing for is fighting Orks right now.

A Minion Formation as described on Page 124 of Enemies of the Imperium consists of 3-5 Minions and 1 Handler, but can be made larger at the GM's discretion.

Best way to do this is to play "Against the savages" with a couple of batches of disposable characters and tweak a little bit the enemies in order to learn the system and gauge the power levels.

The first time I ran the adventure a single ork killed the whole squad :-)

A Minion Formation as described on Page 124 of Enemies of the Imperium consists of 3-5 Minions and 1 Handler, but can be made larger at the GM's discretion.

Aha! Thank you; I've not gotten around to picking up that book yet. I presume for the more badass minions like Clawed Fiends it's more like 1 per Handler, as well?

Best way to do this is to play "Against the savages" with a couple of batches of disposable characters and tweak a little bit the enemies in order to learn the system and gauge the power levels.

The first time I ran the adventure a single ork killed the whole squad :-)

There's an idea, though we've already stated an original campaign.

It's funny you say the second bit; in the first session the squad got the drop on a group of 4 Boys and killed them all without even suffering any damage. Surprise rounds at range with Long Lases are nasty.

Longlas and Triplex Lasguns are probably the best Ork hunting weapons out there. Armed with those or Boltguns, you'll slaughter Orks.