Sphere of Power

Attention, Big Bads: this is probably the point where you should give up.

So, your Player Character just got an Invincibility Power-Up, anime hero unlocked a Super Mode, or your essay is due in an hour and you drink a Red Bull. How do you represent the sudden increase in power? With circles and spheres.

It can be in the form of a debris cloud that envelops the character, a Chunky Updraft that circles the character like electrons around an atom, a full-body halo that radiates from him, a barrier of any stripe, a cyclone spiraling upwards, or maybe Instant Runes following the character around like a celestial spotlight. Point is, it's got circles and therefore it must be powerful.

This is possibly because a circle (in 2D) and sphere (in 3D) are the shapes any equally distributed outward pressure will form.

Not to be confused with the Sphere of Destruction.

Examples of Sphere of Power include:

Anime and Manga

Tengen Toppa Gurren Lagann twists this trope with Spiral Power, which creates... well, you can probably guess.
Mew and Mewtwo in Pokémon the First Movie.
The Rasengan and all its variants in Naruto.
- Tailed Beast also fire compressed balls of chakra out of their mouths. In fact, this was what the Rasengan was based on.
- The Hyuga clan can use a technique called the Eight Trigrams Palm Rotation which releases large amounts of chakra from their body and spins in order to block most attacks.
Hayate's ascension as the Queen of the Night Sky in Magical Girl Lyrical Nanoha, which was marked by her being surrounded by a sphere of white light.
When pissed off, the Phoenix King Saffron from Ranma ½ begins radiating a sphere of blinding-white heat which he then uses to build up his ultimate technique.
Dragonball Z combines this with Sphere of Destruction when Cell attains his Perfect form, rendering himself temporarily invulnerable and taking out a chunk of countryside to boot.
- Also, Android #17's barrier of ki forms a perfect sphere around him.
- Frieza was surrounded by one of as part of his own final transformation; in the Budokai games, the entire process is abbreviated into him calling it up, then cracking out of it like an eggshell.
Mahou Sensei Negima's Ku Fe emits one in a really intense arm wrestle.
Shows up in Kenichi: The Mightiest Disciple whenever the Seikuken is activated.

Live Action TV

The Kamen Rider Dragon Knight transformation effect looks a great deal like the page image. The sphere forms, the circle (actually two in one) appears at waist level, and they slowly flip, suiting the Rider as they pass over. When the circles have gone 180° and are one again, the effect ends. A monster or rival Rider unfortunate enough to be too close when the henshin field bursts forth from the belt will be thrown backwards.
- Several Kamen Riders get a sphere effect. And these spheres are crazy impenetrable, repelling any charging monster or its weaponfire.

Tabletop RPG

The Dungeons and Dragons spell Prismatic Sphere, with all the powers of Rainbow Motif.

Video Games

The spellcasting effect in Final Fantasy VII looks like this.
Okami has this appear several times. The Saotomi orbs which circle princess Fuse and later you, the Vengeance Slips which protect you from attack, the Godhood barriers, the Bead weapons which circle Amaterasu's neck and the various enemies with orbiting stone heads/skulls.
- And of course, Yami, the God of Evil is what seems to be a gray fish in a spherical fishbowl with a Humongous Mecha outer shell. The latter comes from being the creator of Technology.
In Sonic the Hedgehog, Tails's super form features four superpowerful Flickies (magical birds) that encircle him and constantly rotate around him, destroying anything that comes near him.
In Sonic Adventure, Super Sonic gets one in the true final level.
In Kingdom Hearts II whenever a character levels up they are briefly surrounded by a sphere.
- The Aero spell, typically an air-elemental offensive spell in Final Fantasy, is instead a spherical shield in Kingdom Hearts.
Taken to its logical extreme in Final Fantasy X in which the entire levelling system is based around spheres.
Pikachu's Final Smash attack in Super Smash Bros. Brawl turns him into ball lightning. Large, fast, and almost uncontrollable by any but the most skilled players.
- Sonic's is the same, but much easier to control.
The Art of the Invincible Fire Wheel in the NES Ninja Gaiden games, which is a set of three fireballs that orbit Ryu's body for a short amount of time.
Mega Man X's Rolling Shield projects a sphere of pressure around him, protecting him from harm.
- For that matter, the classic Mega Man uses the Reverse Shrapnel variety for his shields: Leaf Shield, Jewel Shield, Skull Shield, Junk Shield (which can also be fired outwards,) Crystal Shield...
Two notable examples from the Tales series are Sync's Harrowing Gale and Tison's Infernal Lord Mystic Artes.

Western Animation

As the pic shows, Aang from Avatar: The Last Airbender once made one from all four elements, it's the reason fans now call him Planet Aang.
In Transformers: Beast Machines, the heroic Maximals are surrounded by personal spheres of light when their Sparks are temporarily empowered by the Matrix, allowing them to plow through the Vehicons like lightning-fast wrecking balls. Sadly, it doesn't last.