At the basic level, the spell creates a two-meter-by-two-meter barrier. The Increase Area effect can be added to add up to two meters in length and width (but not depth) for each time the effect is chosen. The barrier can be shaped as desired by the caster.
| Increase Are Effect | | Drain | | Surface | | Cube side | | Side of 2,4m high cuboid | | Sphere radius | | Dome radius |
| 0 | 5 | 4 m² | 0,82 m | 0,39 m | 0,56 m | 0,65 m |
| 1 | 6 | 16 m² | 1,63 m | 1,31 m | 1,13 m | 1,3 m |
| 2 | 7 | 36 m² | 2,45 m | 2,47 m | 1,69 m | 1,95 m |
| 3 | 8 | 64 m² | 3,27 m | 3,74 m | 2,26 m | 2,61 m |
I don't really see the point in making a barrier that doesn't completely surround the area you want to protect, since astral entities don't really care about walls and other obstacles in the real world. The only exception would be an elevator shaft or passage that leads below the earth's surface, since the earth blocks astral movement. Or at least it did, in previous editions.
you could use mana barrier across a doorway or similar to block people entering with active spells or foci or etc.
make it harder for an opponent magician on the physical plane to cast spells at you.
In case of Mana Barrier vs. Ward, note that the spell creates a barrier with rating (Magic + net hits), whereas the ritual creates a barrier with rating (net hits) only.
FYI, in the latest PDF revision, Ward (the ritual) creates a barrier with rating (leader's Magic rating)+net hits
Good points. But since the description of the spell starts with "Want a spirit-free room?", at least it is meant to be used for that purpose too.If you want your mana barrier (spell) to stop actually astral entities then it seem as if you need to cast it on the astral plane rather than on the physical plane.
To me the only saving grace of the ritual is the size of the barrier: up to 50 m³ times the sum of the participants’ Magic ratings.You also have the Circle of Protection Ritual.
Then you have the lodge of course, which, as far as I can tell, has no maximum rating. Provided you can pay for the materials of course. The only limiting factor is the availability of those materials I guess.
If you want your mana barrier (spell) to stop actually astral entities then it seem as if you need to cast it on the astral plane rather than on the physical plane.