Lightweight Beams

Lightweight Beams
Availability
Introduced in	Age of Empires IV - Season Four
Civilization	All civilizations
Age	Imperial Age
Research
Researched at	Siege Workshop
Wood	300
Gold	400
Research time	60 seconds
Effect
Battering Rams and Cheirosiphons attack +20% faster and their field construction takes -50% time Towers of the Sultan attack +20% faster

Lightweight Beams is a technology in Age of Empires IV introduced in Season Four, that can be researched at the Siege Workshop in the Imperial Age. Once researched, Battering Rams (or Cheirosiphons for the Byzantines) attack 20% faster, and are constructed 100% faster in the field. The Rate of Fire increase also applies to the Tower of the Sultan.

Civilization bonuses

• Abbasid Dynasty: Research speeds are +15%/+20% faster while Golden Age tiers 2/3 are active
• Ayyubids: Research speeds are 25% faster while Golden Age tier 2 is active
• Byzantines: Research speeds are 30% faster per water level at buildings within the influence of a Cistern with the Dialecticus ability active.
• Chinese and Zhu Xi's Legacy: The technology researches 150% faster when the Siege Workshop is supervised by an Imperial Official. For Zhu Xi's Legacy, this can be improved to 300% faster after researching Regional Inspection.
• Delhi Sultanate: The technology is free, but takes 12x as long to research (720 seconds instead of 60 seconds). The research time can be further decreased by 50% if a Scholar is garrisoned inside the Siege Workshop at which it is researched.
• House of Lancaster: This technology is 15% cheaper if King's College has been constructed.
• Japanese: Research speed is +150% faster when researched at a Siege Workshop with a Yorishiro garrisoned.
• Malians: Technologies take less time to research based on how much gold has been obtained through trade.
• Mongols: Can research the improved version for an additional 500 stone to provide an additional 10% attack speed and -25% field construction time (+30% attack speed, -75% build time total)

Changelog

• Originally, the cost of Lightweight Beams was 100 wood, 225 gold and it took 45 seconds to research. With update 7.0.5861, the cost was increased to 300 wood, 400 gold and the research time was increased to 60 seconds. The Mongol improved version cost was proportionally increased from 325 stone to 700 stone, and the Delhi Sultanate research time was proportionally increased from 585 seconds to 780 seconds. With update 10.0.576, the Delhi Sultanate research time scaling was changed from 13x to 12x (to match other Imperial Age technologies), bringing its research time down to 720 seconds. With update 15.1.6970, the cost of the Mongol improved version was reduced to 500 stone.
• With patch 8.2.218, Lightweight Beams attack speed bonus reduced from +40% to 20%.