Targeting this spell uses the Innate Attack (Gaze) skill.

Summon Swarm [59] 
    Diseased Rat Swarm [38.82] 
        Innate Attack (Piercing) 2d [31.5] 
            Mobile (Move 3) [+120%] 
            Homing (Night Vision 5) [+55%] 
            Does damage to feet [+0%] 
                Unless target falls over, then it's torso 
            Environmental (Must be Standing on Floor/Ground) [-10%] 
        Innate Attack (Toxic) 2 HP [7.32] 
            Follow-Up (Piercing Innate Attack) [+55%] 
            Cyclic (20 cycles at 1 day intervals, Mildly Contagious) [+120%] 
            Resistible (HT-2) [-20%] 
    Bat Swarm: Innate Attack (Piercing) 1d [6.5] 
        Mobile (Move 10) [+400%] 
        Homing (Scanning Sense (Sonar)) [+70%] 
        Overhead [+30%] 
        Alternate Attack [x1/5] 
    Spider Swarm: Innate Attack (Toxic) 1d [6.3] 
        Contact Agent [+150%] 
            Spiders climb inside clothes and armor 
        Cyclic (4 cycles at 10 second intervals [+200%] 
        Mobile (Move 2) [+80%] 
        Homing (Ordinary Vision) [+50%] 
        Delay (Fixed, 1 second) [+0%] 
            They need time to climb all-over target 
        Alternate Attack [x1/5] 
    Flying Insect Swarm: Innate Attack (Piercing) 1d [6.5] 
        Contact Agent [+150%] 
            Insects climb inside clothes and armor 
        Symptoms (Moderate Pain after 2/3 HP) [+20%] 
        Mobile (Move 6) [+240%] 
        Homing (Ultravision) [+60%] 
        Overhead [+30%] 
        Delay (Fixed, 1 second) [+0%] 
            They need time to climb all-over target 
        Alternate Attack [x1/5] 
    Area Effect (2 yard radius) [+50%] 
    Persistent [+40%] 
    Selective Area [+20%] 
    Takes Extra Time 1 [-10%] 
    Magical [-10%] 
    Spell Components [-40%] 
        Must say "swarm" in Latin 
        Must gesture with hands 
        Must tap foot 
        Must hold a square of red cloth ($0.02) 
Level 2 [69] 
    Increase Area Effect by 1 step [+50%] 
    Add Extended Duration (x3) [+20%] 
Levels 3-5 [80/91/100.68] 
    Increase Area Effect by 1 step [+50%] 
    Increase Extended Duration by 1 step [+20%] 
Levels 6-7 [104/107] 
    Increase Extended Duration by 1 step [+20%]