I am thinking particularly the other elements like water, air,earth. Has anyone actually done this in their games yet? and if so what have you added?
after all the powers and qualities are only effectively descriptors for play.
Yup. Tried all three. It all depends if you count them as elements/energy or as materials. Depends on how your hero uses them more or less. I also used Hallmark Power for them sometimes. As you said, they are mostly used as descriptors.
I changed Cold to Water for one hero. She still deals cold damage when attacking with the power, just to interact properly with other mechanics, but Principle of Water has a very different application than Principle of Cold would.
Well, Earth already pretty much exists in the Stone (Materials) Power, so that one’s covered.
Weather (Element/Energy) can easily be used for Air, and perhaps Water.
Plants and Metal (both Materials) can be used for the Asian Elements Wood and Metal, respectively. Though @deanjday didn’t ask about those, I always hate to see them go ignored.
As for making completely new ones, I would respectfully disagree with @JoeSteeloak; I think that, seeing as all the existing Element/Energy Powers are more Energy-like (i.e. they’re mostly just forces, not actual physical objects, e.g. Fire, Cold, Cosmic, etc.), Air, Earth, and Water should be used as Materials Powers. Now, of course, if one needs to use one of them as an Element/Energy for mechanical reasons, by all means do so. I (literally) can’t stop you.* I’m merely saying what I think makes the most logical sense.
*Well, I guess I could detonate that bomb I hid in your house . . .
Haha well you are not disagreeing with me as I said it depends if you count them as elements or materials 
Not sure I would count Air as either Elemental or Material though.
so as a sort of exercise, I went through all the characters I’ve built and compiled the custom powers (look in the second tab). didn’t end up with much in the way of “other elements” like you’re looking for.
I did expect a higher percentage to be Signature Weapons/Vehicles (as those are the ones you rename anyway), but it turns out several of the things that really should have been Sig Weapons flavor-wise work better mechanically as whatever energy/materials they’re emulating.
the two I really couldn’t categorize both boil down to Time Control, which… feels mostly like a Psychic power, but with a little Mobility/Self Control/Materials/Energy mixed in.
I took Necromantic as a sort of off flavour “Darkness”.
I have used a bone material power for a necromancer character i made and a luck manipulation hallmark power, thought i could also see it being psychic
I’ve added a few. For the nameless one from the video game Planescape-Torment I added the self-control power “Without Mortality.” When starting up Dr Medico I made the “Life Energy” energy power. Also “Haka” as an energy type when starting up Haka, and the Hallmark power “Extreme Luck,” for Setback.
If I remember correctly, I just gave my Necromancer Robotics and renamed it Necromancy. The difference is totally narrative, so she gets all the Minion Maker abilities.
Also used Cold for Water for another hero, and marked it as such on the sheet so she has normal damage-type interactions with other characters. Changing the principle from Cold to Water is actually much more interesting.
I’ve done (and seen done) similar things with Gadgets. People have renamed it things like “mini-artifacts” or “Artifice” to turn gadgets from a tech-based power to a series of magical trinkets.
Generally, when builing Heroes, I find it helpful to think in Power classes rather than individual Powers.
This also helps to realize that sometimes, the Power you have in mind is maybe a bit to broad, and should in fact be several Powers.
Example:
I made a reality shaper type scientist Hero, who would generate macroscopic quantum effects to bend the laws of spacetime around himself. There is no Power for ‘Spacetime meddling’, obviously. Adding that as a hallmark power (or even shoehorning it into the ‘energy’ class, as some sort of a natural force) seems the straightforward route, but I realized that would basically create a catch-all megapower.
So I split it up into its self-control aspect (Intangibility, renamed superposition), the tech-equipment part (Inventions) and the spatial uncertainty (Teleportation) as well as the slight temporal advantage (Awareness).
I realize that this is ‘using up’ a lot of powers, but feels so much more rounded, and in the spirit of how the game works.
Yes. One character described the ability to redirect kinetic energy, sort of a physical Absorption, so I have created a new energy power called Kinetic. It can be used like other energy powers, to defend, attack etc.
I’m looking to add a “negative/darkness” energy type like from City of Heroes. It is anti-life and makes the target sluggish and clumsy. I had tried to make it fit with Infernal, but it really is almost the opposite. It is like the cold side of evil instead of the hot side.
Our games have mostly ignored the book definition of Infernal and just used it as generic “unpleasant magic” effects, which has included hellfire, life-draining/pain and shadow/darkness effects depending on who was using it. Similarly, Radiant gets used for mundane lasers at least as often as “good magic” functions.
The principle danger with adding a bunch of new element/energy categories instead of broadening existing ones is that each new type reduces the many abilities that let you ignore, invert, or boost off of a single E/E type. It’s already hard to benefit from those with any kind of reliability (barring combos with your own powers) and it’s worse the more E/E types there are to choose from.
All-new powers and qualities also cause some minor complication when picking Red abilities. You really can’t shove all the new stuff in the Hallmark category for that - that Red chart is written so that three of the four options are restricted to Signature Weapon or Vehicle, and the one other choice isn’t particularly appropriate for many things you might add as new powers, like (say) Tunneling or actual Shadow Manipulation as its own thing.
I have no intention of adding this to a generic SCRPG game. It is specifically added to my Two Tickets to Paragon campaign because nearly a third of the villains use it and there are other groups that use Infernal and they are very distinct in flavor and capabilities. Otherwise, I believe you are right and most of the other types get lumped under energy in my way of thinking.
The lack of a canon “shadow” power (either as an e/e or materials) is an odd gap, but I suspect C&A weren’t the biggest Legion of Super-Heroes readers. Their loss, many a young lad grew up on Shadow Lass cheesecake. 
Outside of her I can’t think of many heroes who do shadows. Villains, sure, Eclipso and the Shade spring to mind, but heroes are few and far between.
There’s also Alan Scott’s kid, Obsidian.
Forgot that one. Marvel probably has a mutant or two as well - haven’t paid much attention to them since New Mutants was still in single digits. And Cloak of Cloak & Dagger probably qualifies.
On the villain side, that Karkull guy (who I’d never heard of) that corrupted Obsidian seems to be another shadow user, and Hawkman’s old foe the Shadow Thief as well.
Yeah, I’ve not heard of him before either, although apparently he is the villain who was responsible for making the JSA semi-immortal — I was aware that someone did that, but I didn’t know that it was him.
I found another hero that used shadow or darkness powers: Darksheer from the PC game “Noctropolis.” It was originally published in 1994 by Electronic Arts, and I believe you can still download it.
Out of curiosity, what is your take on gravity manipulation?
My first thought was to either put it close to magnetism (which is, essentially, Metal-bending) or Telekinesis depending on how it is used.
Come to think of it, Density control and Flying are not totally off the list either.
So that makes for another nice set of Powers assembled around a shared concept, and begging to be shifted around for various alternate iterations of the hero, right?
For me it’s just one of many possible flavors of Cosmic. You could take other powers (TK, Flying, etc.) to represent reliable uses of it beyond “mangle things with gravitic force” but the main reason for doing so mechanically would be to access different Red abilities and to limit your vulnerability to having your Cosmic die stepped down or removed by twists.
I think that Telekinesis covers the majority of the potential applications of a “Gravity Manipulation” power.
I would ask the GM before the game starts if they’ll let you use Telekinesis to create “pure force” that directly “crushes”/“smashes”/etc. your target. If the GM says “No, you can only use Telekinesis to move/throw/lift/drop stuff”, then I would take another power for those direct applications of “pure gravitic force”, most likely Cosmic.
Either way, supplementing Telekinesis with Metal or with any other Materials power seems redundant to me.
For gravity-powered personal movement, I would take Flying, Leaping, and/or Wall-Crawling. Those are all easy to justify with “Gravity Manipulation” as a descriptor.
Either Density Control or a combination of Strength and Vitality would work if you want the character to use the same pseudo-scientific explanation of “accustomed to higher gravity” for enhanced durability and strength as characters like John Carter of Mars or Superman.
Sidebar: I once created a character for a superhero RPG who was basically a mash-up of the titular characters from Doctor Who and House, MD, a cranky super-intelligent alien from a “low-gravity” world. They were physically disabled while on Earth, suffering the same mechanical penalties that Earth’s natives would suffer on “high-gravity” worlds, so they had a debilitating addiction to painkillers, and they walked with a cane that they had souped-up into a sci-fi multi-tool and arsenal, like a sonic screwdriver crossed with a Star Trek phaser.
Shadow Lass, AKA “Umbra”, depending on the era.
Minor Nitpick: James Robinson’s (excellent) 1990s Starman series and subsequent The Shade miniseries changed The Shade into more of an antihero type.
Cloak absolutely qualifies. He’s directly connected to the DarkForce Dimension.
TV Tropes is useful for finding stuff like this:
Casting A Shadow
Most darkness/shadow controllers in superhero comics draw their power from a single extraplanar source. In the DCU, it’s the Shadowlands, and in the Marvel Universe, it’s the DarkForce Dimension.
In most Dungeons & Dragons cosmologies, The Negative Energy Plane and The Shadowfel are similarly described and utilized.
Characters who haven’t been mentioned yet include:
The Darkness (Image Comics)
Grue (Worm)
The King In Black (Marvel Comics)
Kirigan (Shadow & Bone)
Clan Lasombra (Vampire: The Masquerade)
Nightshade (DC Comics)
Raven (Teen Titans cartoon adaptation, not the original comics version)
I played a darkness/shadow controller in my first Sentinel Comics campaign. I took Telekinesis so that I could create mobile force constructs out of darkness the same way that Green Lantern rings create them out of light. I took Infernal to represent attacking people with dark “anti-life, anti-light” energy in a more “direct” way, though I seriously considered using Cold for that instead. Teleportation was my travel power, jumping in and out of shadows and using a “darkness dimension” as a shortcut through space. I took Invisibility to vanish into shadows and to extend shadows to obscure myself. I couldn’t actually become a shadow, or else I would’ve taken Intangibility, and I would’ve considered Wall-Crawling. One could also justify creating ropes/chains from the shadows for Swinging. I know that I at least considered Imposing + Presence to represent intimidating people by making the darkness show them their worst fears, but I don’t remember if I actually wound up doing that or not. I know that I didn’t wind up taking Remote Viewing to represent spying on people through shadows, but I did consider that option as well.
Welcome aboard. Nice to see a new account that’s definitively a human being and not some weird AI thing or simple-minded spambot.
Sure, but the bulk of his career (and it’s a long one) has cast him as a villain pure and simple, and even as an antihero he’s still on the (ahem) shady side by comic book hero standards. He didn’t start out as a shadow-wielding hero, or even antihero.
Similarly, while Cloak is clearly a shadow user (which I wasn’t questioning), his status as a hero was pretty shaky early on. I haven’t read much of him (or Dagger) since the first year or two of their existence and they’ve probably changed a lot since, but both were more on the “fairly ruthless vigilantes hunting drug dealers” side of things in their origin than squeaky clean moral paragons.
Still the only shadow-wielding hero-from-day-one I’ve read (The Darkness from Image definitely does not qualify as a hero, and only one iteration of Raven really leans that way over “dark magic user”), but I think it’s worth noting that her shadow powers are just that - she makes darkness. Unlike the majority of “shadow supers” her power isn’t generally associated with things beyond darkness, no cold or life draining or necromancy or other dark magic stuff, and certainly no portals to other dimensions or teleporting or any of the other tricks that are often part of a package “shadow powers” deal. It’s a pretty notable difference between her and the rest.
Whether that’s solely due to many LoSH members having rather narrow, specialized power sets is debatable, but it does keep her from having the kind of creep factor many shadow supers do. Most of the time she’s clearly heroic without the baggage of (say) Raven or Cloak and his fellow DarkForce users. The couple of times I’ve seen writers try to tie some dubious mystical stuff to her it hasn’t worked well or stuck around long.
Sidebar: I once created a character for a superhero RPG who was basically a mash-up of the titular characters from Doctor Who and House, MD , a cranky super-intelligent alien from a “low-gravity” world. They were physically disabled while on Earth, suffering the same mechanical penalties that Earth’s natives would suffer on “high-gravity” worlds, so they had a debilitating addiction to painkillers, and they walked with a cane that they had souped-up into a sci-fi multi-tool and arsenal, like a sonic screwdriver crossed with a Star Trek phaser.
you might want to look for Witch Doctor a US comic book created by writer Brandon Seifert and artist Lukas Ketner.
House as Dr. Strange = analytical diagnosis to find a good way to remove a curse and a metric ton of sarcastic world-weary cynicism
This thread got me to thinking about Doctor Demiurge, an experiment in fitting some seemingly far-out character concepts another player had into the game mechanics. Fun opportunity to flex some creative and system mastery muscles for me, and the player really seemed to like it. My commentary throughout the post might be of some help when it comes to helping a new player craft a PC that fits their personal vision.
The campaign he was for also included the significantly less imaginative Phade as my PC. FrivYeti was playing as Charlie-Foxtrot as well but I don’t have a copy of his character - although you can see everyone’s over here:
The game met a sudden and untimely end due to GM health issues, but it was a fun time while it lasted. AFAIK Gruagach (said GM) hasn’t been heard from since last June, hopefully he’s recovering okay.