Shield

The Shield, also known as Barrier (バリア) in Japan, Normal Shield or Barrier Shield, is a power-up item in the Sonic the Hedgehog series. First introduced in Sonic the Hedgehog (1991), the Shield is obtained by breaking an Item Box with a blue or dark green circular symbol on the monitor. It is the first and original of all shield type power-ups.

The power-up itself envelops the playing character in a spherical barrier which protects the wearer from attacks or damage so that the player would not lose Rings or a life if they are hit without Rings. Its color varies from blue, green and grey depending on what game it is in. Unlike its successors, it does not have any additional abilities to grant to the wearer.

Description
The protection of Shield varies on certain forms. It is able to negate damage taken from enemies, spikes, and some other level hazards. After hitting one of these hazards, the Shield disappears and the player is usually sent flying backwards slightly without losing Rings. Shields will not protect the player from falling into bottomless pits, being crushed, or losing a life due to running out of time. It will also not protect a player from drowning, although unlike the elemental shields, it will at least remain in place if the player goes underwater.

Under normal circumstances, the Shield can be obtained by breaking Item Boxes/Monitors displaying the Shield's icon in the respective games or other objects containing power-ups. Once obtained, the Shield will surround the player character until it is broken or the level is completed.

The Shield's color has varied thought the series without any logical reason. In the early games it was usually a light blue color, while since Sonic Adventure, it has usually been dark green. In Sonic Generations, it is simply a transparent white bubble, but in most appearances it is translucent with a blue or green tint.

Sonic the Hedgehog (1991)
The Shield debuted in the original 16-bit version of Sonic the Hedgehog. In the game, it can be collected from Monitors with the Shield icon on them. The Shield is colored a washed-out blue and flashes around Sonic. Due to the "Spike Bug" in the original version of the game, spikes are able to bypass the player's protection and can cause them to lose their Shield, Rings, and life in rapid succession.

The 8-bit version of the game also features Shields. These Shields are smaller and brighter in color than their 16-bit counterparts, and will spin around the player. Neither shield will protect the player from drowning in the underwater sections of Labyrinth Zone.

Sonic the Hedgehog 2
In Sonic the Hedgehog 2, the Shield has a darker tint of blue than in the first game, but still functions the same. The Shield also appears in the two-player mode of the game as a random power-up. In Knuckles the Echidna in Sonic the Hedgehog 2, the Shield is colored grey instead of blue.

Sonic the Hedgehog CD
In Sonic the Hedgehog CD, the Shield's appearance is identical to that of the original Sonic the Hedgehog and its abilities remain identical to that of those in the previous installments.

Knuckles' Chaotix
In Knuckles' Chaotix, the Shield is a fairly common power-up. It looks and works similarly to the previous games, with an added spinning effect, but is only given to whichever of the two player-controlled characters breaks the Monitor, leaving the other vulnerable to attack.

Sonic the Fighters
In Sonic the Fighters, the traditional Shield does not appear, but instead the game features the Barrier mechanic, which the fighters can use to protect themselves from attacks. Both fighters starts each fight with five Barriers, and each Barrier can only withstand a certain amount of damage before breaking.

Sonic 3D Blast
In Sonic 3D Blast, as well as the standard Shield, there are three other types of Shield. First, there is the Blue Shield which can negate electrical attacks and obstacles, similar to the Thunder Shield. The second is the Red Shield, which works like the Flame Shield by negating fire attacks. The last is the Gold Shield, which allows the player to perform the Blast Attack, a move similar to the Homing Attack.

It is worth noting that the Flickies following the player also receive a small Shield when the player obtains one; the Flickies' Shields do not disappear upon hitting an obstacle unless Sonic also hits the obstacle.

Sonic Blast
In Sonic Blast, the Shield is again a Monitor power-up. In this game, it is small compared to the playable character. However, there are some monitors with question marks that gave one of the eight power-ups in the game at random, including the Shield.

Sonic Adventure
In Sonic Adventure and its later iteration Sonic Adventure DX: Director's Cut, the Shield makes its first appearance in a 3D game title. The color of the Shield is now a dark green instead of blue, but its function remains unchanged.

Sonic Pocket Adventure
In Sonic the Hedgehog Pocket Adventure, the Shield has become one of the general monitor power-ups once more, where it is again colored light blue. The Shield can also be obtained during multiplayer mode.

Sonic Adventure 2
In Sonic Adventure 2 and its later iteration Sonic Adventure 2: Battle, the dark green Shield appears once again. In this game, if the player has ninety Rings on hand when they touch a Point Marker, the player will earn a Shield automatically.

Sonic Advance series
In the Sonic Advance games, the Shield retains its green appearance, but is instead referred to as the Barrier. In all three games, it can be found in normal or floating Item Boxes.

Sonic Heroes
In Sonic Heroes, the Shield is once more called the Barrier. Its appearance in this game is smaller and more colorful, though it retains its green tint, even turning almost invisible sometimes. It can be found in both Item Boxes and the floating balloon variants.

Sonic Rush series
In Sonic Rush and Sonic Rush Adventure, the dark green Shields are once again called the Barrier. These power-ups are once again included in Item Boxes and balloon variants as well.

Sonic Rivals series
In Sonic Rivals and its sequel Sonic Rivals 2, the Shield is replaced by a POwer-Up called the "Fire Shield". This power-up creates a barrier of fire around the user which is functionally like the Shield, but will disappear after a certain amount of time. To use it, the player must obtain a Fire element Power-Up and must be ahead of their rival in the stage.

Shadow the Hedgehog
In Shadow the Hedgehog, the Shield reappeared as the normal, dark green Barrier again. In addition, the game introduced a new variant called the Heat Barrier, which hurts surrounding enemies.

Sonic the Hedgehog (2006)
In Sonic the Hedgehog (2006), the Shield itself did not appear despite being listed in the game's manual, suggesting it was once included in the game but was later scrapped. This thus makes Sonic the Hedgehog (2006) one of the only main series Sonic games not to feature the basic Shield.

The game featured the Thunder Shield as an ability called Thunder Guard, triggered by the Yellow Gem. The game also introduces an exclusive shield called the Energy Field. In Action Stages such as Dusty Desert and Tropical Jungle, where Sonic has to escort Princess Elise, the player can use the Energy Field to prevent Sonic from sinking into quicksand and water, though the field does not negate damage.

Sonic Riders: Zero Gravity
In Sonic Riders: Zero Gravity, the Shield power-up only appears in Survival Battle. Its purpose remains much the same as in past games; the Shield protects the player from one attack, preventing the user from losing Hit Points (in Sudden Death mode) or allowing an opponent to gain a point for hitting the player (in Points Battle). The Shield will instantly dissipate if the player falls off the field, however.

Sonic Unleashed
In the PlayStation 3 and Xbox 360 versions of Sonic Unleashed, a different type of Shield is featured. This shield appears when performing Guard as Sonic the Werehog, and will neutralize all damage Sonic receives from certain attacks. However, each hit it blocks consumes a part of the Shield Gauge, and if it drained completely, the Shield will break. The player is able to increase the size of the Shield Gauge by collecting Chaos Orbs to increase its level.

Sonic & All-Stars Racing series
In Sonic & Sega All-Stars Racing and Sonic & All-Stars Racing Transformed, one of the Item Box power-ups is a dark green Energy Shield that can be activated after obtaining it. When used, the Energy Shield works identically to the Shield in previous games.

Sonic the Hedgehog 4
The Shield makes an appearance in both episodes of Sonic the Hedgehog 4, although it is still colored dark green. If Sonic transforms into Super Sonic while the Shield is active, the Shield stays around Super Sonic.

Sonic Colors
The Shield made a reappearance in the Nintendo DS version of Sonic Colors, and is identical in function and appearance to the Shields from previous games.

Sonic Generations
In Sonic Generations, the Shields make an appearance in both versions of the game. In the console/PC version of the game, the Shield resembles a white orb like the Aqua Shield, but its icon shows it as being dark green. It can only be obtained if the player buys it as a Skill from the Skill Shop. The player can then equip it and activate it manually whenever desired during a Stage. The Shield can only be used by Classic Sonic when playing through Act 1 of any Stage.

In the Nintendo 3DS version of the game, the Shield can be found normally inside Item Boxes, or obtained as an extra skill after playing Versus Mode online.

Sonic Jump series
In Sonic Jump, Sonic Jump 2, the 2012 remake of Sonic Jump, and Sonic Jump Fever, the dark green Shield appears as a collectible power-up. The 2012 remake includes different Shields as well.

Sonic Dash
In Sonic Dash, dark green Shields are included in Item Boxes. When the player obtains it, it will temporarily protect them from taking damage from spikes or Badniks. However, it will disappear after a certain period of time; its lifespan can be upgraded by spending Rings.

Sonic Runners
In Sonic Runners, the Shield regains its light blue color scheme from the earlier games. Shields can be found in Item Boxes as regular power-ups, but they can also be bought as Equippable Items to be used during the level, where they cost 1,000 Rings.

Adventures of Sonic the Hedgehog
In the episode "Robotnik's Pyramid Scheme" the Mummified Hedgehog gave Sonic a necklace that creates a Blue Shield, protecting him from Robotnik's immortality.

Sonic X (comic)
In Archie Comic's Sonic X #10, Sonic finds a shield monitor on top of a large loop in Green Hill Zone. Upon first obtaining it, he is confused by it and tries to outrun it, which fails. He loses the Shield upon being hit by Dr. Eggman's checkered wrecking ball.

Archie Comics
In Archie's Sonic the Hedgehog comics, Sonic is seen using a similar shield during issue 227, as part of the Genesis arc. When Sonic, Sally and Boomer enter Scrap Brain Zone and come across Doctor Eggman with large mechanic pillars, Sonic suddenly got trapped of blue forcefield around him. He uses it during the fight against Eggman's machine and as Antoine arrives into the Eggman's machine, Sonic finishes the battle and after that, the shield disappears.

Trivia

 * In Sonic the Hedgehog 2, while playing as Super Sonic, the Shield's icon in the monitor changes to a golden-yellow, matching Super Sonic's color scheme; if the player obtains the Shield, it will be the same golden-yellow color. This is due Sonic and shield sharing the same color palette in the game. The same thing can happen in Knuckles the Echidna in Sonic the Hedgehog 2, where the shield starts glowing pink just like Super Knuckles does.
 * In Sonic the Hedgehog (2006), while the game's manual states that the Shield can be obtained during gameplay, it in fact cannot.