オニオンソード [onion sword] in Japanese.
Final Fantasy III

Stats: ATK 156, ACC 100, STR +5, VIT +5, INT +5, MND +5, AGI +5, weight 1
Use: ONK
Drop: (1.5% chance) Green Dragon, Red Dragon, Yellow Dragon
Type: Sword
Final Fantasy IV
Stats: ATK 2xLV, ACC LV+50, STR +LV/3
Equip: Cecil, Kain
Buy: - (sell: 1,000 gil)
Obtain: give Red Tail to Tail Collector
Final Fantasy Tactics
Stats: ATK 50, Parry 15% (when available)
Range: horizontal 1, vertical up 2, vertical down 3
Equip (job): Onion Knight
Equip (character): -
Equip (enemy): -
Buy: - (sell: 5 gil)
Obtain: Melee Mode multiplayer
Description: A blade forged for swordsmen who have master every technique and achieved knighthood's most exalted rank.
Other: can be used with Dual Wield and Doublehand
Crystal Chronicles
Stats: STR +1
Obtain: Veo Lu Sluice, cycle 3
Other: an Artifact
Airborne Brigade

SSR+
Type: Sword, Element: -, Growth: Slow, Cost: 42
Attack: 17,500 (lv1), ? (lv200), ? (lv230), ? (lv260), ? (lv290), ? (lv320)
Defense: 17,230 (lv1), ? (lv200), ? (lv230), ? (lv260), ? (lv290), ? (lv320)
Obtain: ?
SSR
Type: Sword, Element: -, Growth: Slow, Cost: 34
Attack: 12,660 (lv1), ? (lv200), ? (lv220), ? (lv240), 67,046 (lv260), ? (lv280)
Defense: 12,650 (lv1), ? (lv200), ? (lv220), ? (lv240), 66,011 (lv260), ? (lv280)
Obtain: ?
Category: Equipment