Originally Posted by ghost_warlock
And, again, even 1st-level adventurers are trained with a basic proficiency in whatever weapon they wield - sword or spell. They are not utter noobs, not commoners, and should not be threatened by vermin. The game is Dungeons & Dragons, not Cornfields and Cottontails.
So the point is mostly that dire rats (and other low-level critters) are undersized and underpowered for the level of scary they're described as being (by fluff and CR).
What if they were four feet at the shoulder?