Tyranids: Hive Tyrant

The Hive Tyrant is a massive Tyranid bioform and the primary battlefield commander of the Tyranid swarm, enforcing the will of the Hive Mind. As a powerful "synapse creature," it orchestrates the actions of lesser Tyranid organisms, preventing them from succumbing to their animalistic instincts. Towering over even a Space Marine Dreadnought, these psychic monsters are highly customizable, adapting both physically and tactically to dominate the battlefield. 
Role and abilities
Synaptic commander: The Hive Tyrant acts as a crucial link to the Hive Mind, relaying its strategic commands to the swarm. Its presence creates a "synaptic link" that Lesser Tyranids can tap into, allowing for instantaneous and coordinated action. The destruction of a Hive Tyrant can cause widespread disarray and confusion among nearby Tyranid forces.
Potent psyker: Hive Tyrants possess powerful psychic abilities derived from the collective gestalt consciousness of the Hive Mind. They use these powers to shatter enemy morale, invigorate the swarm, and unleash devastating psychic attacks. They are also immune to the influence of Chaos Daemons.
Apex predator: Every part of a Hive Tyrant is a weapon designed for killing. They are monstrously strong, capable of shattering solid rock, and can be equipped with a terrifying array of bio-weapons for both close combat and ranged attacks.
Practical immortality: The Hive Mind can regenerate its fallen leaders. If a Hive Tyrant is killed, the Hive Mind can absorb its genetic material and grow a new, often more adapted, one. This makes each Hive Tyrant effectively immortal. 
Physical characteristics
Hive Tyrants are monstrous organisms that stand over 6 meters tall and can weigh up to 6 tons. 
Chitinous shell: A distinctive and resilient shell covers the creature, providing it with extensive armor.
Skeletal underbody: Below the hard carapace is a hideous, skeletal understructure.
Bio-chimneys: The shell is often studded with "chimneys" on its back, a common feature among many Tyranid organisms.
Prehensile tail: A serpent-like tail allows for dynamic posing and provides another lethal appendage. 
Customization and variants
In battle, the Hive Tyrant can be equipped and adapted to various tactical roles:
Weapon options: They can be armed with a variety of bio-weapons, including:
Scything talons
Rending claws
Boneswords and lash whips
Heavy venom cannons, which fire explosive, corrosive projectiles
Stranglethorn cannons, which launch pods of choking tendrils
Biomorphs: Adaptations like adrenal glands can increase their speed and charge, while toxin sacs add venom to their attacks.
The Swarmlord: The most advanced and cunning variant of the Hive Tyrant, possessing superior intelligence and acting as the Hive Mind's ultimate strategist.
Winged Hive Tyrant ("Flyrant"): An aerial variant with leathery wings, allowing it to dominate the skies and provide mobile synapse coverage across the battlefield.