Titan Of Innovation

Over a span of 7 days you can make a medium, large, or gargantuan enclosed mech, which only you can use,  with base traits based on the following chart:

Medium, 6 M5 Materials, 10 Energy, 4 Capacity, 4 Heat Threshold, it's maximum HP is equal to your maximum HP as if your hit dice were one size larger for HP calculations, it's AC is 13 + your Dexterity Modifier
Large, 12 M5 Materials, 8 Energy, 6 Capacity, 5 Heat Threshold, it's maximum HP is equal to your maximum HP as if you rolled the max on all hit dice it's AC is 15 + your Dexterity Modifier
Gargantuan, 24 M5 Materials, 4 Energy, 12 Capacity, 10 Heat Threshold, it's Maximum HP is double your maximum HP, It's AC is 18

While within such a mech, your maximum and current HP and AC are replaced by it's maximum and current HP and AC, you can only be healed up to 30 HP, and may choose to have your creature type be treated as a humanoid or construct for the purposes of effects.
If you are at or below 50 hp while in one of these suits, you make all attacks at Disadvantage and your movement speed is halved. If your HP is higher than 30, removing a suit sets your hp to 30.

A mech can be equipped with the following augments that are labeled between Tier 1 to Tier 3, which need to be crafted first. Exchanging one crafted augment for another takes an amount of days equal to 1 times the number of sizes larger than medium that the mech is, as well as a DC 25 Tinker's Tools check each day.

Crafting an augment takes an amount of days equal to its Tier times the number of sizes that the mech is larger than medium, and an amount of M5 Materials equal to 9 times the number of sizes that the mech is larger than medium. Tier 3 augments cost an additional Unique material that cannot be replaced by an Omnicraft Token. Each day that you are crafting, you must succeed on a DC 30 Tinker's Tools check.

Overheat Mechanic: When you reach the maximum heat threshold of a suit you take 20 damage at the start of each of your turns, for each point of heat above the maximum threshold you take that damage an additional time.

Energy Recharges fully after 8 hours , or you may use one energy cell as an action to regain 1 energy.
Over the course of a minute you can make a Tinker's Tools check in order to restore an amount of HP to the mech equal to the roll's total.

Tier 1
Costs 1 capacity each when equipped
Life Support: Pick one environmental hazard(Extreme Heat, Extreme Cold, Vaccuum, extreme pressure etc.) you gain immunity to the effects of the hazard for as long as you have energy. You can pick this more than once.

O2 Pack: The mech automatically generates clean breathable air as long as you have energy.

Integrated Weapon: When this attachment is made choose one weapon which you own, the weapon becomes inseparable from the mech for as long as you remain attuned to the weapon. The weapon increases, or decreases in size to match the size of the mech. If you are larger than medium the weapon gains the reach property if it lacks it.

Integrated Armor: Using an attunement slot, all mechs can be upgraded in the form of infusing it with a magical armor of any type, giving you its benefits except the base AC of the armor is 16+(1*number of sizes larger than medium that the mech is) as well as the ability to don and doff them as an Action for medium and large sized ones. Gargantuan ones take 10 minutes to don or doff.

Tier 2
Costs 2 capacity each when equipped
Tracking Darts: You may spend 2 energy to make a ranged weapon attack with a 150/300ft range using intelligence with expertise to hit, on a hit you can track the precise location of the creature for as long as it is in range. You can have up to 3 darts active at a time, and may target creatures that are obscured but not in cover as if they weren't.

Heat Sink: Heat is reduced by 1 at the start of your turn if you didn't spend any energy since the start of your last turn.

Integrated Item: Using an attunement slot, all mechs can be upgraded in the form of infusing it with a wondrous item the mech gains the activated, and passive abilties of the item except for those that define health, ac, immunities, resistances, sentience, or indestructibility.

Demoralizing Entry Music: At the start of each of your turns you may spend 1 energy to have any number of target creatures that can hear you within 120 ft. make a wisdom saving throw against your Spellcasting DC. On a failure, they become frightened for 1 minute. A creature can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success. If a creature's saving throw is successful or the effect ends for it, the creature is immune to your Demoralizing Entry Music for the next 24 hours.

Aerodynamic Reconfiguration: You may spend 2 energy as a bonus action to triple your flight speed for up to 2 hours, in this state you cannot take attack actions, or magic actions. You can end this state as an action.

Target Designation System: This Attachment is considered an upgrade for one vehicle chosen on creation. The Vehicle cannot be piloted manually or automatically by outside sources and is controlled by the wearer of the mech instead. In initiative it shares the wearers position, taking its turn immediately after the wearer, if the wearer is incapacitated or gives no commands, the vehicle does nothing.

Tier 3
Costs 4 capacity each when equipped.

Overclock Chip: As a Bonus Action, you may channel your inner fire into the suit, gaining an amount of energy up to the maximum capacity. However you also gain twice that amount as Heat.

Liquid Nitrogen Cooling: Once per day, you gain a single use of your cooling system, which you activate by using a Bonus Action, that reduces your Heat by half.

Advanced Firewall: Your actions cannot be dictated by outside sources, if something would force you to take an action the suit locks down and forces you to do nothing but taking the dodge action instead.

Particle Dispersion Cannon: One of your arms is replaced with a ranged weapon allowing you to spend 2 Energy and gain 2 Heat to replace an attack with a ranged attack that uses your Spell to Hit, it deals 4d8+10 force damage.

Thermal Amplifier: Your heat threshold is reduced by 3, overheat deals double damage to you. While you are overheating you add xd6[fire damage] to all attacks where x is the number of heat stacks above the max you have accrued.

Size Adaptation: Your heat threshold is reduced by 3, when you use an ability or cast a spell you may spend one energy and for every size above medium that you are the range or area of effect is increased by 50ft.

Standard Equipment
The Large, and Gargantuan mechs naturally possess an unarmed strike that deals 2d6 magical bludgeoning damage and uses the wearer's Intelligence Modifier instead of its Strength Modifier. Additionally, your reach with that is 10 ft. The wearer is considered proficient in it if they have proficiency in computers, and expertise if they have expertise.

Transportation
A medium mech can be transported in the form of a suitcase.
As an action a large mech can be called in through an orbital satellite that follows your position, and drops it, provided that there is an unoccupied space available. It may crash through up to 2 feet of solid material.
A gargantuan mech can only be transported by a gargantuan vehicle.