[Immaculate]

Pythium is a fun and powerful nation- one of my favorite. Somewhere around there is an AAR where the player uses pythium to absolutely stomp Abyssia then proceed to win the game. I don't know where the link is though. And yes, practice with communions. Power of the sphere is very important.

Since you are new, i will give you an example set-up you should probably try in single-person. Its for what is called a reverse communion.

Set up N communion members. Theurgs are sufficient.

Round 1:
Have the first N-1 cast communion slave.
With the last one, cast communion master.

Round 2:
Have the first N-1 cast stellar cascades or something.
Have the last one cast power of the spheres. (now everyone has their paths boosted by 1 and will take less fatigue from spell casting)

Round 3:
Have the first one cast light of the northern star. Now their astral is (starting value) +2.
Everyone else casts soul slay or enslave mind. You've turned paralyze spam into soul slay or enslave mind spam for only 2 astral gems.
Potentially your master can cast things like twist fate or other personal buffs to protect or otherwise buff your slaves.

Round 4:
Profit.

This is my favorite sort of communion, is easy and is very safe.

Alternative:
You could accelerate the whole thing if you forge a crystal matrix for your master. Consider:

Round 1:
Have the first N-1 cast communion slave.
With the last one, armed with a crystal matrix, casts power of the spheres.

Round 2:
Have the first one casts light of the norther star. Now its only round two and all their astral is (starting value) +2.
Everyone else casts soul slay or enslave mind. You've turned paralyze spam into soul slay or enslave mind spam for only 2 astral gems and the price of the crystal matrix and if you've done it on round two.

Round 3:
Profit.