Yep! You should check out the rules for conjurations in the back of the PH2, they'll help a lot. Also, figure out with your DM now whether they'll allow the spirit to move vertically, to save a headache later. (There's no clear RAW either way, although it can definitely float in the air.)
It isn't, actually, that's why there's a lot of confusion about it. It would be such an easy thing to add to the power, too!Also, you should read the rules for Call Spirit Companion.
Things like the OPs question are answered there.
Call Spirit Companion said:Your soul reaches out to your spirit friend, which faithfully appears at your side.
At-WillConjuration, Primal![]()
Minor Action Close burst 20
Effect: You conjure your spirit companion in an unoccupied square in the burst. The spirit lasts until you fall unconscious or until you dismiss it as a minor action. The spirit occupies 1 square. Enemies cannot move through its space, but allies can. When you take a move action, you can also move the spirit a number of squares equal to your speed.
The spirit can be targeted by melee or ranged attacks, although it lacks hit points. If a single melee or ranged attack deals damage to the spirit equal to 10 + one-half your level or higher, the spirit disappears, and you take damage equal to 5 + one-half your level. Otherwise, the spirit is unaffected by the attack.
CONJURATION
A conjuration you create uses these rules, unless a
power description says otherwise.
...
✦ Your Defenses: Normally, a conjuration cannot be attacked or physically affected. If a conjuration can be attacked or physically affected, it uses your defenses. Unless an attack specifically targets conjurations, only the attack’s damage (not including ongoing damage) affects the conjuration.