Spoog Heavy Tank

The Spoog heavy tank was one of the earliest designs of Biological Tanks, built on planetary Mauluo by one particular nation as an answer to a particularly well fortified location, and break the stalemate that was happening in that war. 

With a much lower level of 'technology', the Spoog was not too far from its natural form. Though the evidence of extensive modifications from its original species was obvious, such as the growing of many new organs designed to fire large payloads similar to a cannon, it was still in possession of structures like a digestive tract and various vestigial structures. Though quite suboptimal for an organic tank which was to be crewed by Harki it would go on to break the stalemate it was designed to break and essentially won the war for that nation.

The Spoog had a large body covered with a very thick chitin that was hard to penetrate even with most types of biological cannons. It did have a large weak point on its legs though, if a Spoog was hit by most kinds of heavy weapons in the joints of their legs it would cripple their mobility. This was only found later in the war when it was already too late to turn the war back in enemy favor.

It came too early for the technology of rotating cannons, so its cannon had to me mounted directly to its body. It could use complex muscular tension to traverse the cannon slightly without turning the entire tank, but the whole organism would have to turn when flanked. Later tank designs were built with these rotating cannons. There were also problems with its accuracy especially while on the move as its nervous system did not automatically compensate for movements.

The tank had a massive crew of 12. All of its crew were located inside the tank and protected by its thick armour. It had one crew member located next to the joints of each of its 6 legs, dedicated to the movement of their specific legs. They had to coordinate the entire organism's walk cycle manually using messages sent through the tank's nervous system, which was incredibly hard to do and required intense training. There was also a commander and gunner, a spotter who would use all of the tank's senses to locate enemy threats (the senses were also used by the commander to navigate normally, but the spotter was tasked with spotting enemy threats at longer distances), and several other crew members dedicated to ensuring its many systems were functioning properly. Each crew member had their own hatch located close to their seating place. All of the crew were linked to each other through the nervous system...

Because its main energy generator was its digestive tract, the tank required food to operate. It would often scavenge the battlefield after a battle to eat dead purposed organisms, harki or animals. After the war, they instead ate mostly farm animals which were fed to the tanks by the harki keeping them. Sometimes, criminals were fed to the tanks.

The sounds produced by its various organ systems were often distracting to the crew. Their crew stations were also often hot and wet due to being internal to a large organism, and the tank's microbiome meant that the crew members were at risk of infection. Crew members also quite often inherited a microbiome similar to that of the tank. Later, purposed organisms meant for cleaning would clean out its insides to make the conditions better for the crew. In the first few tanks, rather than being held in their own glands, the crew were simply placed within the areas between organ systems with dedicated stations for interacting with its nervous system. They often fell out of these dedicated locations, and weapons that could penetrate the tank's armour often also killed the crew especially when its glands designed to manufacture gunpowder were destroyed. When crew members were displaced too far from their dedicated locations, it might have caused them to lose their air supply and suffocate.

The Spoog's key strength was that it still retained its reproductive system. The nation that operated Spoogs thus kept a large number of them to maintain a large viable population. As they got old, they were deployed and the younger ones took over the task of reproduction. Reproductive systems were located closer to the front because if they were likely to be hit they would be unlikely to ever reproduce again, even if not hit. In female spoogs, their chitin armour layer had to be designedeto account for heavy expansion, as their womb normally takes up little space but when pregnant it expands massively, which the armour would need to expand to accommodate. This species undergoes live birth and has a roughly equal population of males to females. They also give birth to relatively large young, who are already much larger than a harkas.

Many of these shortcomings were rectified in later organic tanks, but despite the many disadvantages of the Spoog species, it has proven the worth for organic tanks and caused many others in the future to build more and better ones.