Sassafras

Sassafras is a boss that was added with the release of the game.

Design
Sassafras has a hexagon beige base with an "Eye" in the center. "Eye" has a shape of black circle and a yellow circle inside. "Eye" faces wherever Sassafras is currently moving. Around the six auto-turrets are located, three Destroyer turrets, three Builder turrets, alternating after each other. On each outer side of the base, a minion spawner is located.

Minion which boss spawns have a hexagon base, with the same "Eye" in the center. They also have gunner turret.

Technical
Sassafras spawns destroyer bullets and blocks, but both have low bullet health and can be easily penetrated/dodged. The main firepower of the boss are the minions: respawned every 15 seconds, maximum 6. Minions attack from all sides, and have decent damage, but can be killed within ~6 seconds.

Spawning
Spawns by a randomizer.

Countering
Although Sassafras may look powerful, in fact, it is not a strong boss. The most effective tanks are bullet spammers. It moves too slow to rush into traps, Sassafras minions can overwhelm your drones and minions. Bullet spammers can kill it easily.

In order to do so, one must first eliminate all the minions. No need to retreat, just try to take them out one by one, or if they are in groups focus the closest group to, but the longest from Sassafras. Do not get distracted, as minions have good damage, and spreading bullets on all sides is also effective way to finish them off.

After all of the minions are dead, attack the boss. You will easily penetrate the blocks and bullets, just do not forget to move left-right to trick boss into missing more bullets. It will take a lot of damage, approximately 30% of the health bar. After that, again kill the minions which respawned and attack the boss. It will very soon be dead.