Mana Accellerator? Mystic Egg?

[DGDobrev]

Ok, here's short info of all abilities:

Mystic egg - the dragon steals an egg from somewhere that hatches on the next round, providing new troops (unless it is destroyed).
Mana accelerator - adds movement points and mana
Crushing blow - hits and pushes targets lvl 1-3 back 1-3 squares (depends on ability lvl)
Treasure Seeker - digs up chests and altars on the battlefield.
Stone Wall - creates a 3-square stone wall
Ball of Lightning - ability that creates a ball of lightning with 3 charges. Each charge inflicts damage based on the total troop health.
Dragon Dive - mass attack ability, pushes the closest enemies of all levels back 1 square (if possible)
battle frenzy - mass attack in 5x5 square area. Inflicts astral damage to all units there, including allies.
lava flow - attacks up to 8 enemy targets with lava, inflicting fire damage.

I'll add it in the info thread as well. I cannot go in-depth, because there are numerous ways an ability can go - less rest, more damage, etc. You can't master all abilities too, so decide which ones will be the most important and go for them.