Torso Upgrades

Secret Compartment You have a built-in compartment in which you integrate a small bag of holding. Every dimensional aspect about this bag of holding is halved, so it cannot hold more than 250 pounds and increases your body weight by 8 pounds. This compartment cannot be seen by any other creature except when you interact with it in front of them. Since it is integrated it cannot be stolen. You have advantage on any sleight of hand skill checks you make while interacting with this upgrade.

Forged Heart You magically enhance your heart to increase your endurance and to recover from exhaustion faster. All your non-magical movement speeds are increased by 10 ft. Finishing a short rest reduces your exhaustion level by 1, whereas finishing a long rest reduces your exhaustion level by 2 instead of the usual 1. As an action you can expend 4 charges to hasten your Forged Heart. This increases your non-magical movement speeds by another 20 ft for 1 minute.

Monocyte Breeder You attach a separate Monocyte Breeder to your spleen to improve your immune system. You gain immunity to diseases and resistance to poison damage. You can also inject those monocytes into a willing creature that is immunocompromised. You can expend 2 charges as an action to cast Cure Wounds. For every additional 1 charge expended, the healing increases by 1d8. Additionally, you can expend 2 charges to cure a willing creature you touch from any diseases.

Arcane Respiratory System You implant new lungs and upgrade your chemosensors. You gain the ability to breathe underwater and are immune to poison damage from toxic clouds. Furthermore you gain advantage on perception checks relying on smell. From now on you are under the influence of the Detect Poison and Disease spell.

Modified Endoskeleton You modify the composition of your endoskeleton, making it more resistant and allowing it to change its properties from solid to flexible if the need arises. You gain resistance to bludgeoning damage. Furthermore, the hit point bonus you get from constitution each level is now 1.5 times your constitution modifier rounded up.

Synthetic Growth Accelerator Prerequisite: 5th level Artificer

You've disposed of some useless organs and installed a new upgrade in place that tackles one of your limitations: Longevity. You finish a long rest after only 4 hours of sleep. You otherwise obey all the rules for a long rest; only the duration is changed. You increase your constitution ability score by 2 and it's maximum to 22. You do not age anymore and cannot be aged magically.