Summon Swarm Spell:
You summon a swarm of bats, rats, or spiders (your choice), which attacks all other creatures within its area. (You may summon the swarm so that it shares the area of other creatures.) If no living creatures are within its area, the swarm attacks or pursues the nearest creature as best it can. The caster has no control over its target or direction of travel.
Looking for a survey of how you would play this with a summoned swarm.
Question 1
xx
x32
1
x=swarm
3=creature already in swarm
1 and 2=creatures outside swarm
A)swarm must remain where it is attacking 3
B)swarm may move to engulf/attack 1 and 2 as well as 3
Question 2
xx 3
xx12
A)swarm my only move and engulf 1
B)swarm may move to engulf 1, 2 and 3