Onager (Age of Empires II)

This article is about the unit in Age of Empires II. For the unit in Age of Mythology, see Onager (Age of Mythology).

Onager
Unit information
Introduced in	The Age of Kings
Type	Siege unit
Civilization	See description
Age	Imperial Age
Training
Trained at	Siege Workshop
Wood	160
Gold	135
Training time	46 seconds
Statistics
Hit points	60
Attack	50 melee
Attack bonuses	+45 vs Building +12 vs Siege weapon
Blast radius	1.25
Rate of Fire	6
Frame delay	0
Range	8
Minimum range	3
Accuracy	100%
Projectile speed	3.5
Melee armor	0
Pierce armor	7
Armor classes	Siege weapon
Speed	0.6
Line of Sight	10
Unit evolution
Upgraded from	Mangonel
Upgrades to	Siege Onager
Upgrade cost	1,450 food, 1,000 gold
Upgrade time	150 seconds

“	Stronger than Mangonel. Wheeled siege weapon used to attack a small mass of units.	”
—Age of Empires II description

The Onager is a ranged siege unit in Age of Empires II that can be trained at the Siege Workshop once the Imperial Age is reached. It is primarily used against large groups of enemies. Its high attack and splash damage make it a powerful unit, especially against archers and slow-moving units. Its main offsets are its projectile speed, minimum range, and tendency to harm friendly units caught in its blast. Onagers can attack ground and destroy trees.

Onagers are available to all civilizations except for the Huns and Turks.

Tactics

Onagers are devastating against archers and slow-moving units, but cannot defend themselves against most melee units. Therefore, they need to be guarded in most situations. Archers are often used because the player's melee units can be damaged by their own Onagers if they are not careful. But archers do not cover the Onager's main weakness adequately, which is cavalry. Therefore, Onagers are also often paired with Halberdiers. That combination is used often with the Celts and Slavs, who both have bonuses affecting Onagers and Halberdiers.

Onagers are effective against naval units. The AI will often send out Onagers as a shore defense to protect its buildings.

While the Onager upgrade is fairly expensive at 800 food and a whopping 500 gold, it provides more attack, +1 range, +1 pierce armor, and slightly more HP. Since The Forgotten, Onagers are able to cut down trees, making them valuable in maps with large areas of forests like Black Forest by enabling the player to attack from behind a forest. It is visually distinguishable by a thicker more reinforced appearance. Overall it is a worthwhile upgrade when multiple Mangonels are being deployed.

Further statistics

Unit strengths and weaknesses
Strong vs.	Buildings, Villagers, archers, Scorpions, Battering Rams, Trebuchets, units in dense formations
Weak vs.	Melee units especially Magyar Huszars and other melee cavalry, Mangudai, Woad Raiders, Condottieri, Eagle Warriors, Bombard Cannons
Upgrades
Hit points	Furor Celtica (+40%, Celts only)
Attack	Siege Engineers (+20% attack against buildings)  Chemistry (+1)  Torsion Engines (increases blast damage radius, Ethiopians only)
Range	Siege Engineers (+1)  Shinkichon (+1, Koreans only)
Armor	Ironclad (+4/+0, Teutons only)
Movement Speed	Drill (+50%, Mongols only)
Conversion defense	Faith  Heresy
Upgrades	Siege Onager

Civilization bonuses

• Aztecs: Onagers are created 11% faster.
• Bulgarians: Upgrading to Siege Onagers costs 50% less food.
• Burmese: Researching Faith is 50% cheaper.
• Celts: Onagers fire 25% faster. Onagers can convert herdables even if enemy units are next to them.
• Chinese: Technologies that benefit Onagers are 20% cheaper.
• Italians: Researching Chemistry is 33% cheaper.
• Portuguese: Onagers cost 20% less gold. Upgrades that benefit Onagers are researched 30% faster.
• Slavs: Onagers are 15% cheaper.
• Tatars: Onagers deal +25% bonus damage from cliffs and elevations.

Team bonuses

• A team containing Celts: Onagers are created and upgraded 20% faster.
• A team containing Koreans: Onagers minimum range reduced.
• A team containing Malians: Researching Chemistry and Siege Engineers is 80% faster.
• A team containing Teutons: Onagers are more resistant to conversion.
• A team containing Lithuanians: Researching Heresy and Faith is 20% faster.

Changelog

The Age of Kings

• Onagers move at a speed of 0.5.
• Researching Chemistry reduces the projectile speed from 3.5 to 2.9.

The Conquerors

• Onagers now move at a speed of 0.6.
• Onagers gain +12 bonus damage against siege weapons.
• Heresy introduced.
• Celts: Furor Celtica introduced. It gives Onagers +50% HP.
• Mongols: Drill introduced.
• Koreans: Shinkichon initially gives Onagers +2 range. With patch 1.0b, the effect was reduced to +1.
• A team containing Koreans: Onagers have +1 range.

The Forgotten

• Onagers can cut down trees.
• Researching Chemistry does not affect the projectile speed anymore.
• Celts: Furor Celtica now gives +40% HP to Onagers.
• Teutons: Ironclad introduced.
• A team containing Koreans: Onagers minimum range reduced by 2 (instead of +1 range).

Definitive Edition

• Bulgarians: With update 42848, Siege Workshop technologies cost -50% food.
• Portuguese: With update 42848, technologies are researched 30% faster.

History

“	The onager was an improvement of the mangonel; it was larger, more powerful, and hurled a heavier payload for greater distance.	”
—Age of Empires II manual

In reality, the onager was invented long before the mangonel, by the Ancient Romans. The Onager is credited as being the first Torsion Spring or Petraria Arcatinus-type catapult, as all catapults before that are called Ballistae and/or Scorpions.

The word onager derives from the Greek onagros, meaning "wild ass". It was named after the famously untameable onager or Asian wild ass (Equus hemionus), because it was said that the engine threw rocks as hard as the animal kicked.

Gallery

A group of Onagers

The Mangonel line, with the Onager in the middle

Onagers can cut down trees since The Forgotten.

Add a photo to this gallery