First draft...
Wizard Wight CR 2
XP 600
CE Medium undead
Init +3; Senses blindsight 50 ft., Perception +7
Aura spell-doom (50 ft., DC 14)
Defense
AC 15, touch 13, flat-footed 12 (+3 Dex, +2 natural)
hp 18 (4d8)
Fort +3, Ref +4, Will +4
Offense
Speed 35 ft.
Melee claw +4 (1d8 plus poison)
Space 5 ft., Reach 5 ft.
Statistics
Str 11, Dex 17, Con - , Int 14, Wis 11, Cha 14
Base Atk +3, CMB +3, CMD 16
Feats Power Attack, Weapon Focus (claw)
Skills Climb +7, Intimidate +9, Knowledge (arcana) +9, Spellcraft +9, Stealth +10
Special Abilities
Poison (Ex)
Necrotic Venom: Claw – injury; save Fort DC 14; frequency 1/round for 6 rounds; effect 1d2 Con; cure 1 save.
Spell-Doom Aura (Su)
Any creature that casts an arcane or divine spell or spell-like ability within the wizard wight's aura suffers 2d4 damage; a DC 14 Fortitude save halves the damage.
Ecology
Environment Warm forests and swamps
Organization Solitary
Treasure Incidental
I'm especially uncertain about the spell-doom aura's conversion. Also, did I do the skills right?