Ancient Construct

Overview
The Ancient Construct is a boss added in the 2.2 Patch. The Construct can easily wipe out a group of Heavy Tanks with its laser attacks that almost ignore armor. It is also immune to stun effects and freeze effects, and highly resistant to all damage except explosive.

That's the bad news. The good news is that the Ancient Construct can drop Units, the rare and prized Sinister and Dexter Fragments that can be obtained can be extremely versatile to an extent. It's worth noting "Sinister" and "Dexter" are old words for "left" and "right" respectively, relating to the Construct's arms.

Percival says in a later mission this monstrosity used to be an ancient garbage cleaner, and by attacking him, you awakened the ancient security defense systems, the Ancient Sentinel, which makes Morgan really annoyed thinking he lost many troops fighting a garbage cleaner.

Also the vertical laser only attacks 2 units if there is a blocking unit in the front

The Construct re-spawns in 168 hours (1 week/seven days), so you can continue to battle him for a chance at the following rewards:

Rewards
After defeating this boss one can obtain:
 * Sinister Fragment (Unit), 1% drop rate
 * Dexter Fragment (Unit), 5% drop rate
 * Sinister Fragment (Unit), 1% drop rate
 * Dexter Fragment (Unit), 5% drop rate
 * Sinister Fragment (Unit), 1% drop rate
 * Dexter Fragment (Unit), 5% drop rate
 * Dexter Fragment (Unit), 5% drop rate

Strategy
Players have found several strategies that work to defeat the Ancient Construct. There are a few things to keep in mind before trying any of them, however:


 * The Ancient Construct can wipe out even tanks like swatting a fly, be prepared to lose a few units. It is NOT recommended for players unprepared for the hospital bill or those who do not own a significant force to take the Construct down.
 * The chances of a player winning with an insignificant army, such as Rank one units, is frighteningly low. Players inadequately equipped are not recommended to attempt without being prepared to lose most of their formation, or suffer a defeat. Exceptions are : Mega Tanks and Super Tanks in place of Heavier Tanks, and a Radio Tech to replace a Tank Killer.

This is an alternative strategy with little to no casualties and without the use of but instead :

Method for low-rank units:

Trivia

 * "Sinister" and "Dexter" are old words for "left" and "right", relating to the Construct's arms
 * The Ancient Construct is a garbage removal robot.

Updates
2.85 Patch
 * Both the Ancient Construct and the Ancient Sentinel spawn in their own encounters if you are level 50 or above and defeated the Construct at least once.

2.2 Patch
 * Added.