Here is the full list of all 22 Zahalia: The Curse of Zezor achievements.
Kill 1,000 Monsters
Recovered the Red Crystal
Kill 500 Monsters
Recovered the Blue Crystal
Kill 100 Monsters
Regrew the Forest
Recovered the Green Crystal
Recovered the Purple Crystal
Recovered the Yellow Crystal
Recovered the Orange Crystal
Recovered the Silver Crystal
Hold 999 Zil
Recovered One Dark Crystal
Recovered Two Dark Crystals
Recovered Three Dark Crystals
Recovered Four Dark Crystals
Recovered Five Dark Crystals
Recovered Six Dark Crystals
Recovered All the Dark Crystals
Found all five of the missing brothers
Defeat the Evil Wizard Zezor
Defeat the Evil Wizard Zezor for Good