IIRC = If I recall correctly, a CYA measure in case you are wrong
In the Manual on page 5 it lists the blessing effects.
Though there is a discrepency. I'll post them here so you don't have to RTFM
This is based off the initial magic levels of a Nation/Themes pretender. This is hardwired into your nation and even if you Empower or your Pretender dies and the value is changed for his magic, the blessing will stay the same as when the Pretender was created.
ALL - Morale +3
Fire 4 - Attack Skill +2
Fire 6 - Attack Skill +3
Fire 8 - Attack Skill +4
Fire 9 - Flaming Weapons (8 AP Fire Damage added to weapons)
Fire 10 - Attack Skill +5
Air 4 - Air Shield (20%)
Air 5 - Air Shield (30%)
Air 6 - Air Shield (40%)
Air 7 - Air Shield (50%)
Air 8 - Air Shield (60%)
Air 9 - Shock resistance (75%), Air Shield (70%)
Air 10 - Air Shield (80%)
Water 4 - Defense Skill +2
Water 6 - Defense Skill +3
Water 8 - Defense Skill +4
Water 9 - Quickness (50%)
Water 10 - Defense Skill +5
Earth 4 - Reinvigoration 2
Earth 6 - Reinvigoration 3
Earth 8 - Reinvigoration 4
Earth 9 - Armor value +4
Earth 10 - Reinvigoration 5
Astral 4 - Magic Resistance +1 (Max 18)
Astral 6 - Magic Resistance +2
Astral 8 - Magic Resistance +3
Astral 9 - Twist Fate (protection from first hit)
Astral 10 - Magic Resistance +4
Death 4 - Lesser Fear
Death 6 - Lesser Fear
Death 8 - Lesser Fear
Death 9 - Life after Death (Non-undead units who die are animated as souless and retain most of their abilities (magic paths) but lose their resistances), Cause Fear* (Undead beings only)
Death 10 - Lesser Fear
Nature 4 - Berserk +1
Nature 6 - Berserk +2
Nature 8 - Berserk +3
Nature 9 - Regeneration, Poison Resistance (50%)
Nature 10 - Berserk +4
Blood 4 - Strength +2
Blood 6 - Strength +3
Blood 8 - Strength +4
Blood 9 - Death Curse (The unit that kills the blessed unit will be *Cursed* as the spell of the same name)
Blood 10 - Strength +5