Lost Odyssey

Numara Atoll is a great place to get your characters to learn all of their skills quickly.

You'll encounter one of two enemies here - Silver Kelolons or Hellshakers. Turn-tail away from the Hellshakers, as they're pretty much a waste of time. You get 8 SP for killing a Silver Kelolon, or twice that with Sed in your party (or an immortal that has learned Double SP), so you can learn skills extremely quickly by battling them. You'll occasionally encounter 2 Kelolons at once, to make things nicer.

Silver Kelolons are very evasive, however, so the only reliable way of killing them is by using the "Gamble" Spirit Magic, which is earned by completing a Kelolon statue mini-game in Tosca. Make sure that your immortals know Reduce Casting Time 1 and 2, so that they can get their spells in before the Kelolons flee.

It's useful to have your characters learn 3 Accessories or 2 Accessories early on, so you can really crunch your way through bracelets and the like. You'll have all 164 skills down before you know it.

By popular demand, here's the list of said skills, as compiled by Captainamerica:

Double Item (From SED)
Absorb Transfer (From JANSEN)
Drain Shower (From JANSEN)
Counter (Combat Teachings)
Spell Counter (Warrior Armband)
Weapon Guard (Sword Teaching)
Absorb Attack (Amulet)
Absorb Magic (Talisman)
MP Guard (From TOLTEN)
Persistence (From TOLTEN)
Counter Guard (From TOLTEN)
Absorb Guard (From TOLTEN)
Guard Heal (Platinum Gauntlet)
Relax (Circlet)
Stand Ready (Knight Code)
Power Guard (From TOLTEN)
Lucky GC Ignore (From SED)
Auto Shield (Golden Gauntlet or From SED)
Auto Barrier (Royal Emblem or From SED)
Auto HP Recovery (White Charm)
Auto MP Recovery (Crystal Fragment)
Double back (Twin Cross)
Counter Up (Black Belt)
Angel Heart (From COOKE)
Resourceful (From SED)
Potion Booster (Herbalist Badge)
Double Gold (From SED)
Double Loot (From SED)
Double EXP (From SED)
Double SP (From SED)
2 Accessories (From JANSEN)
3 Accessories (From SED)
Special Accessory (From SED)
Royal Equipment (From TOLTEN)
Black Staff (From JANSEN)
White Staff (From COOKE)
Factual Analysis (Hawk Eye)
Status Analysis (Search Glasses)
Treasure Analysis (Treasure Glasses)
Ultimate Analysis (From SED)
Critical Heal (Lucky Clover)
Critical Defense (Holy Guard)
Crisis Concentration (Sage Protection)
Crisis Prayer (Happy Flower)
Crisis Attack Boost (Berseker Necklace)
Crisis Defense Boost (Holy Knight Charm)
Lucky 0 Magic Damage (Mimint Ear)
Slot +3 (Awakening Bracelet)
Slot +5 (Freedom Armband)
Slot +10 (1000 Years of Memories)
HP Max 1 (Life Brooch)
HP Max 2 (Toughness Brooch)
HP Max 3 (Gigantes Brooch)
HP Max 4 (Royal Knight Emblem)
MP Max 1 (Mana Earring)
MP Max 2 (Mind Bangle)
MP Max 3 (Sorcerer Bracelet)
MP Max 4 (Kelonga Crown)
Attack Boost 1 (Power Bangle)
Attack Boost 2 (Ogre Bangle)
Defense Boost 1 (Knight Earring)
Defense Boost 2 (Lord Earring)
Magic Defense Boost 1 (Pixie Flower)
Magic Defense Boost 2 (Elfin Charm)
Evade Up (Kelolon Badge)
Double Cast (From JANSEN)
Mental Stability 1 (From COOKE)
Mental Stability 2 (From COOKE)
Reduce Casting Time 1 (From COOKE)
Reduce Casting Time 2 (From COOKE)
MP Conservation (Bracelet of Efficiency)
Lv 1 White Magic (From COOKEorFromJANSEN)
Lv 2 White Magic (From COOKEor From JANSEN)
Lv 3 White Magic (From COOKE)
Lv 4 White Magic (From COOKE)
Lv 5 White Magic (From COOKE)
Lv 6 White Magic (From COOKE)
Lv 7 White Magic (From COOKE)
Lv 8 White Magic (From COOKE)
Lv 1 Black Magic (From JANSEN)
Lv 2 Black Magic (From JANSEN)
Lv 3 Black Magic (From JANSEN)
Lv 4 Black Magic (From JANSEN)
Lv 5 Black Magic (From JANSEN)
Lv 6 Black Magic (From JANSEN)
Lv 7 Black Magic (From JANSEN)
Lv 8 Black Magic (From JANSEN)
Lv 1 Black-White Magic (Novice Earrings)
Lv 2 Black-White Magic (Apprentice Earrings)
Lv 3 Black-White Magic (Adept Earrings)
Lv 4 Black-White Magic (Sorcerer Earrings)
Lv 5 Black-White Magic (Earring of Wisdom)
Lv 6 Black-White Magic (Wisdom Earrings)
Lv 7 Black-White Magic (Sage Earrings)
Lv 8 Black-White Magic (Master Earrings)
Lv 1 Spirit Magic (Eastern Spirit Bandor From MACK)
Lv 2 Spirit Magic (Bronze Spirit Band or From MACK)
Lv 3 Spirit Magic (Red Copper Band or From MACK)
Lv 4 Spirit Magic (Gold Spirit Band or From MACK)
Lv 5 Spirit Magic (Obsidian Spirit Band or From MACK)
Lv 6 Spirit Magic (Diamond Spirit Band or From MACK)
Lv 7 Spirit Magic (Enchanted Necklace or From MACK)
Lv 8 Spirit Magic (Cursed Crest or From MACK)
Lv 1 Composite Magic (Magic Research Report)
Lv 2 Composite Magic (Magic Trial Record)
Lv 3 Composite Magic (Magic Analysis Book)
Lv 4 Composite Magic (Composite Magic Book)
Turn Tail (Turn Tail Shoes or From SED)
Steal (From JANSEN or From SED or Thief Bracelet)
Taunt (From SED or From MACK)
Stand Firm (10 Kilo Weight or From MACK)
Complete Defense (From TOLTEN)
Casting Suport (From COOKE)
Concentrate (From COOKE)
MP Gift (From TOLTEN)
Huge MP Gift (From TOLTEN)
MP Convert (From COOKE)
Prayer (From COOKE)
Lullaby (From TOLTEN)
Award Medal (From TOLTEN)
Magic Seal (From SED)
Counter Seal (From SED)
Power Hit (From MACK or From TOLTEN)
Break Hit (From TOLTEN)
Member Hit (From TOLTEN)
Skill Hit (Scroll Of Secret Skills)
Slot Hit (Scroll Of Balance)
Combo (From MACK)
3 Combo (From MACK)
Ultimate Hit (From TOLTEN)
Cut Down (Scroll of Dissection or From TOLTEN)
All Hit (From TOLTEN)
Wall (From MACK)
Walla (From MACK)
Wallus (From MACK)
Anti-Kelolon (Kelolon Earring)
Anti-Poison (Antidote Brooch)
Anti-Terror (Lionheart)
Anti-Darkness (White Flame Candle)
Anti-Seal (Seal Blocker)
Anti-Freeze (Warm Vest)
Anti-Paralyze (Yellow Band)
Anti-Sleep (Alarm Clock)
Anti-Dizzy (Stabilizzer)
Anti-Curse (Curse Blocker)
Anti-Petrify (Medusa Head)
Anti-Blind (Light Lens)
Freeform (General Pen)
Ailments Resistance (Angel Guard)
Reduce Earth (Earth Charm)
Reduce Fire (Fire Charm)
Reduce Water (Water Charm)
Reduce Air (Air Charm)
Earth Proof (Ochre Earth Amulet)
Fire Proof (Blazing Fire Amulet)
Water Proof (Ice Water Amulet)
Air Proof (High Wind Amulet)
Absorb Earth (Pipot Collar)
Absorb Air (Anereid Feather)
Absorb Fire (Sarah Notebook)
Absorb Water (Blue Dragoneye)
Reduce Elements (Quad Elements Charm)
Nullify Elements (Quad Elements Bracelet)
Absorb Elements (Quand Elements Seal)