note AP cost for spells

glossary.tex

@@ -1053,7 +1053,9 @@ Set the darker die to `\dicef{6}' and roll the other.  If this roll fails, it fa
   When `overspending' on the \glsentrytext{invocation}, the debt is paid in \glsentrytext{ep}.
 
   \Glsfmtplural{tn} depend on how malleable the target is.
-  Earth spells can affect ice far more easily than rocks, and Air spells can whip up a gale easier when outdoors},
+  Earth spells can affect ice far more easily than rocks, and Air spells can whip up a gale easier when outdoors.
+
+  When used in combat, spells cost a number of \glsfmtplural{ap} equal to the \glsentrytext{mp}-cost + 1},
 }
 
 \longnewglossaryentry{alchemy}{