Carrion Summons

There are two parts to this spell. When cast the first part is to open up a small portal which will summon 1 or 2 carrion crawlers to a point designated by the wizard. The second part of the magic mutates the carrion crawlers into larger more vicious versions of themselves. The result is that the wizard now has control over these creature(s) until they are slain, or the spell duration expires. When the spell is cast there is a 35% chance that two will be summoned instead of just one.