A flying Water/ blaster covers gases (air, mostly) and liquids (Water Blast can look like a wide variety of liquids with color customization - lava, acid, ink, blood, etc). /Fire or /Energy can cover plasma/energy... I have no idea what to do for solid manipulation, though. That makes me think shapeshifting and/or transmutation, but we don't have many powers like that.
Water is fairly good for liquid and gas as it dose have a steam power so for solid and plasma id say Ice minpulation for a blaster or for def/corr cold - sonic - time - kin
Cold gives you alot of gases like effects and some solid but drops plasma till epic pools
Sonic covers your gases and solid np as its energy you are making vibrate at such speed it like a solid wall, you don't see them often and it looks cool, mostly a buff set low and mid lvl's
Time again gives you alot of gas like effects, idk if it could also pass for plasma if colored well but it is a great set
Kin actually fits your concept very well as it allows you to change the density of matter making it heavy or light with speed boost and increased density, plasma will be a swing job to make it fit but you get alot of self buff potential
Your concept is really interesting and unique haven't heard any one try something like this before very interestig
There is but one truth. Time is limited. ndnw its over
A dominator might give you the flexibility that you need for something like this, too. Many of the primaries, secondaries, and ancillary pools can represent the four forms of matter you've chosen.
Liquids: Ice Control, Ice Assault, Ice or Leviathan Mastery
Gasses: Gravity or Dark Control might work with the right coloring. Psionic Assault. Psychic Mastery or Mace Mastery (if you just use Scorpion Shield to represent localized wind fields that deflect attacks).
Solids: Earth Control or Plant Control. Earth Assault or Thorny Assault.
Energy/Heat: Pretty much everything else.
Let me never fall into the vulgar mistake of dreaming that I am persecuted whenever I am contradicted.
~Ralph Waldo Emerson
"I was just the one with the most unsolicited sombrero." - Traegus
While I can't suggest a specific combo as the best I would say look at the power sets you have to choose from and try to get the most bang for your buck. The first that immediately comes to mind is Storm Summoning. Why? because it gives you air/gas (Gale, Tornado, Hurricane), Water/Ice (Freezing Rain, Steamy Mist, Snow Storm) and energy (Lightning Storm, Thuderclap). Now pair that with something fire related like say earth control and fire mastery on a controller. you'll basically have all the elements. I know right now water blast is the new hotness but it isn't vital to do so for the liquid end of things.
Jem - Ill/Rad Controller Lv 50+3 Nic - Mind/Psi Dominator Lv 50+3 Lady Liberation - Invuln/SS Tanker Lv 50+1 Invicitx - Demon/Pain Mastermind Lv 50+1 Celeste - Emp/Arch Defender Lv 50+1 Nightsilver - DB/WP Scrapper Lv 34 Dusk Howl - StJ/Regen Brute Lv 32 Kyriani - Time/Energy Defender Lv 41Psifire - FF/Psi Defender Lv 50
Star Lighter - LB/LA Peacebringer Lv 30
Though I should nitpick - while you can probably get away with Ice as a substitute for Water if you're going the classical route (Earth/Fire/Air/Water), it doesn't work for a Solid/Liquid/Gas/Plasma theme. Ice is, by definition, water in solid form, so it doesn't count as a liquid anymore.
Similarly, Steamy Mist is water in gaseous form, not liquid.
That said, I think Freezing Rain (the water's still liquid until it hits the ground) and Hurricane (its description says it's both a rain and windstorm) still count towards Liquid, so it still covering three of the four states all by itself. Pair it with something solid (even Ice), and you're good to go.
Earth/Storm/Fire controller. (Edit : That's basically what Kyriani suggested, so I guess I'm seconding it.)
Among other things, a blast to play on a team and you can alternate Earthquake and Freezing Storm to get good uptime even with SOs.
This isn't really the right forum for this, but I'm not currently VIP so it'll have to do. I have a character concept I love. He's sort of a 'modern' elementalist, blending magic and (pseudo)science. The premise for his powers are that he can manipulate the four states of matter in place of the classic four elements. That's solids, liquids, gasses and plasma/energy (at least for the purposes of his concept).
I came up with this idea to avoid the more generic earth, water, air, fire construct and open up some new build ideas because I felt too compelled to make a Fire/Storm/Earth Controller. Being said, I'd like to get some ideas about which archetypes and powersets to choose! I'm not too fond of Controllers or the Epic ATs (as if they'd work anyway), but I'm open to ideas.