So TheLegendReborn posed a torso building challenge in September (posted here: TLR's Torso Challenge by TLROsborne on DeviantArt) but the basic gist is 16 Toa, all different elements and all different torso builds incorporating specific elements (eg: Inika Torso, Vahki Torso, etc.) so I had a crack at it and here’s the results 
Valo, Toa of Air
Weapon: Gale Twinblades (doubles as propeller blades)
Mask: Mask of Far-Seeing, gives the user the ability to see incredible distances, far exceeding a standard scope (Prog Ares’ Great Mask of Intangibility by Rothanak)
Valo is an older Toa of Air whose ability to fly freely and see great distances make him stand out as an unparalleled scout.
Kinou, Toa of Shadow
Weapon: Shadow Mace & Slasher Claws
Mask: Mask of Hypnosis, allows user to hypnotise through eye-contact, effect lingers for a while and does not require sustained activation like a Great Komau (Great Mask of Shapeshifting by Galva)
A Toa who was once captivated with the raw strength and power of the Makuta species, allowed himself to be drained of light and willingly mutated by their Viruses in an effort to be counted as one of them.
Cistito, Toa of Psionics
Weapon: Psionic Amplifier Frame
Mask: Mask of Rebounding (Great Ruru by Galva)
A proud and powerful Psychic, a botched mission as a young Toa caused her legs to be very frail so she, with the help of a Nynrah Ghost gifted in building prosthetics, developed a Fikou-like walker frame that doubles as an antennae for her Elemental Powers.
Mura, Toa of Fire
Weapon: Melter Cannon
Mask: Kadin, Mask of Flight (Great Kadin by Galva)
With his powerful Melter Cannon and a fire in his belly (literally), this titanic Toa lets nothing stand between him and his Duty.
Deina, Toa of Sonics
Weapon: Bell Hammer
Mask: Mask of Dampening, allows user to dampen wave based attacks (sounds, vibrations, etc.) (Mask of Adaptability by Galva)
A fierce fighter, this noble Toa can dish out massive damage with powerful shockwaves by ringing his Bell Hammer or simply clobber foes with its considerable weight.
“The Hermit”, Toa of Plantlife
Weapon: Slicing Shears
Mask: Mahiki, Mask of Illusions (heavily modified for filtered breathing)
Due to a mishap with a damaged Kanohi Olmak, the Toa known as Tajuma was accidently teleported to Bota Magna. Over time the solitude and sunlight of the Jungle Moon have decayed his mind and bleached his once vibrant armour, now he uses his powers help him camouflage into his surroundings to help him survive against the dangerous fauna and flora.
Fahrad, Toa of Magnetism
Weapon: Gauss Cannon
Mask: Miru, Mask of Levitation (Prototype Miru Nuva Phantoka 2 by Rothanak)
One of the few living Toa of Magnetism, this mighty Toa uses his weapon to fire disks of magnetic Protodermis to defend a small outpost of Fa-Matoran, in hopes of preventing their numbers from dropping any further.
Suto, Toa of Plasma
Weapon: Plasma Greataxe
Mask: Mask of Stasis (Allows user to freeze one target in place, actiavted through touch) (Proto Ignika by Rothanak)
Called in when a job is too large or just needs some good old brute force. With his ability to freeze opponents in place and his superheated axe, which can cut through most armours, Suto is a force to be reckoned with.
Reno, Toa of Iron
Weapon: Iron Knuckle
Mask: Mask of Hardening (Allows user to harden their body to become near indestructable) (Mask of Iron by Galva)
A survivor of the Fe-Matoran massacre, Reno ran and hid as his fellows fell to the Makuta’s attack, now a Toa he seeks to redeem himself and avenge his fallen friends.
Kua, Toa of Lightning
Weapon: Generator Gauntlets
Mask: Kaukau, Mask of Waterbreathing
A young and gusty Toa eager to prove herself. Her gauntlets are constantly charging with Kua’s overflowing electrical energy to add a powerful shock to her punches.
Drin, Toa of Earth
Weapon: Twin-Drill Pickaxe
Mask: Mask of Mineral Detection (Allows user to home in on a chosen mineral or element within a large radius) (Great Azuhi, Mask of Fire by Galva)
The earth is no match for this hulking Toa’s powerful Pick, effortlessly tunnelling to gather Energy Crystal’s to power the Matoran’s homes (and perhaps to stash some away for his own uses and experiments)
Karaka, Toa of Ice
Weapon: Freezer-Burn Blades
Mask: Mask of Friction Control (Inorganic Zatth by KhingK)
By rapidly absorbing the coldness in his arm-mounted blades, Karaka’s weapons glow red-hot and generate enough heat to melt through the thickest ice or armour. His Mask of Friction Control and spiked boots ensures he never slips on ice and even allow him to walk up walls.
Rahu, Toa of Stone
Weapon: Stone Revolver (Designed by Matt Goldberg)
Mask: Mask of Scanning (Allows the user to see a target’s weak points) (Kanohi Bo by Galva)
An experienced Rahi-herder (specifically Kane-Ra), roams from village to village dishing out his own brand of justice where he sees fit.
Nitrix, Toa of Light
Weapon: Energy Enhancement Sword
Mask: Kakama, Mask of Speed (by Galva)
With his Kakama and near perfect control over light, Nitrix is quite possibly the fastest Toa alive. His sword is charged with and enhances the element of the wielder, allowing Nitrix to deliver decisive strikes in the blink of an eye.
Barius, Toa of Gravity
Weapon: Interlocking Twin-Shields
Mask: Mask of Stamina (Gives user near limitless stamina and endurance for a limited time) (Kanohi Bombaik, Great Mask of Molecular Disruption by Rothanak)
Known as the “Impenetrable Fortress”, Toa Barius prides himself on his Twin-Shields and his incredible defensive capabilities.
Hyhati, Toa of Water
Weapon: Deep Sea Anchor (Designed by Kaneczi)
Mask: Kiril, Mask of Regeration (Modelled by MechanicalHands)
Build for deep ocean search and rescue missions, Toa Hyhati’s body has been heavily modified to survive the crushing pressure. Her Kiril allows her to perform repairs on herself without needng to surface.
Thank you so much for checking these guys out! I had a hell of a lot of fun designing and building them and I would definitely recommend you attempt the challenge yourself.
Bonus:
Initial doodles
Rough Sketches
Final Lineup
