diff --git a/combat.tex b/combat.tex
index a7098c50e762c31524090ce1a26f3c040e846269..bbb549b4b021a1f51f26b7181b48af283ae19e9a 100644
--- a/combat.tex
+++ b/combat.tex
@@ -742,12 +742,14 @@ Anyone with the Air Sphere can use this as a Bonus to aid their flight, but will
 
 \pic{Roch_Hercka/conjuration_right}
 
-\subsubsection{Swarms}
-\label{swarms}
+\makeAutoRule{swarms}{Swarms}{each \glsfmttext{hp} occupies one \glsfmttext{step}, which inflicts 1 \glsfmttext{hp} Damage per round. Swarms take up to 1~Damage per attack}
+\index{Swarms}
 
-A river of feral rats, or a buzzing hive of blood-draining insects act a little differently from other combatants.
+This abstract spread of \glspl{hp} can represent a swarm of feral rats, a buzzing hive of blood-draining stirges, or any other tiny thing which can act as a unit.
 We can't track individual bites and stings -- instead the swarm moves as one, but dies separately.
 
+Swarms ignore Partial armour covering (as they can wriggle across the uncovered parts), but cannot attack anyone in Complete armour at all, unless they achieve a \gls{vitalShot}.
+
 \swarm{Rats}{3}{2}{3}{0}
 
 \input{config/rules/swarms.tex}