Moblin

The Moblin is considered the primary muscle of Ganon's evil army. They've been around since the very first Zelda game, and are generally considered to be big, brutish and stupid. Moblins are an anthropomorphic mix of pigs and bulldogs. The Moblin is sometimes viewed as a larger, more elite form of the smaller Bokoblin, or smaller still, the Miniblin.

Quote from The Legend of Zelda: The Minish Cap Spear Moblin  figurine:

"Appears in the Minish Woods, etc. They rush you on sight. They also block head- on attacks with their spears, so circle around to attack."

Quote from The Legend of Zelda: The Minish Cap Bow Moblin  figurine:

"Appears in various areas. They fire arrows at you on sight. Block these with your shield and then close in to attack."

The Legend of Zelda
Moblins first appeared in the original Legend of Zelda as spear-throwing bulldog monsters. Their spears can be blocked by Link's Shield, and they had two key varieties, orange and blue; blue are stronger than orange, as they require more hits to kill. They are most commonly found in forest areas. A few orange Moblins hiding in secret hideouts across Hyrule give you Rupees and deliver the famous quote, "ITS A SECRET TO EVERYBODY".

Notably, there is a Goron in Twilight Princess that states "It's a secret to everybody." when spoken to after the Hyrule Castle has been encased in a barrier.

The Adventure of Link
Later, in The Adventure of Link, Moblins come in many new forms. The top-down view of the original Zelda made them seem short and squat, while the sidescrolling view made them look tall and quite thin. The Moblins in this game are after Link's blood, used to resurrect Ganon, who was previously vanquished by Link. Usually, they will come at Link with defenses up, throwing Spears, while others continue regenerating and coming at Link from both sides of the screen, stealing EXP whenever they touch the player. Their Spears can be blocked with the Shield. They appear as red Moblins, blue Moblins, and orange Moblins. Orange Moblins simply throw their Spears at Link. Red Moblins can't throw their spear, but can stab high or low with it. Blue Moblins can throw their spears and stab low with them.

A Link to the Past
In A Link to the Past, Moblins can only be found in the Dark World, taking the place of the variously-colored soldiers in the Light World. While the Pig Soldiers appear to be Moblins, they are never referred to as such. The ones who are Moblins are the Spear-throwing ones, whose Spears can be blocked by Link's Shield. The ending added to the remake of this game implies that Moblins and Pig Soldiers are actually Ganon's only true Soldiers, and that the other enemies are not on his side. In its Satellaview direct sequel, BS The Legend of Zelda: The Ancient Stone Tablets, there are no Moblins, on account of the fact that the Dark World is not present.

Link's Awakening
Link's Awakening marks the first time a Moblin ever used a sword. Moblins only appear in the Mysterious Forest and the Moblin Hideout, as Sword Moblins (always with shields as well). The Moblins with swords do not wander around aimlessly throwing spears like most of their race, but instead home in on the player like the guards in A Link to the Past. Some Moblins in this game, however, do maintain the tactic of wandering and firing arrows. There is also a Boss named Great Moblin, who kidnapped Madam Meow-Meow's Bow-Wow and resides in the Moblin Hideout. Since Link's Awakening has no relevance to Ganon, these Moblins seem to rule themselves.

Link's Awakening seems to also mark the transition in appearance of Moblins. In older games they resemble bulldogs, but in those releasing later they resemble pigs instead. Interestingly, in addition to bulldog-like Moblins, there are enemies that move and attack exactly like them (both with swords and shields, and bows) that are pig-like. These enemies are found mostly in the area of Tal Tal Heights, near the Wind Fish's Egg.

Ocarina of Time
In Ocarina of Time, Moblins only appear in the Sacred Forest Meadow when Link is an adult. All but one of them will charge at Link with a spear when they spot him; the last one guards the corridor leading to the entrance of the Forest Temple, and when Link approaches it, it will launch shock waves from his club at Link (In the Master Quest version of Ocarina of Time, another Moblin of this type can be found in the Spirit Temple). They are much bigger than any previous Moblins. Although these Moblins are also pig-like in form, they have an appearance similar to a bulldog. Those found in the maze area can be defeated using a large variety of weapons, although the large Moblin wielding a club is best countered with arrows because of their range.

Oracle of Ages and Oracle of Seasons
In Oracle of Ages and Oracle of Seasons, Moblins are one of the most common enemies. They act exactly as they did in Link's Awakening. They come in red and blue variants; The blue ones are usually harder to find and to defeat.

The Great Moblin
The Great Moblin terrorizes the populace in Holodrum and Labrynna—however he is never in two places at once; he is always in the land of the game played first, and then when Link drives him out of that land he goes into the other land, where the player can further humiliate him if they follow him by playing a linked game using a password from the first. He will also recognize Link in that second land, whereas in the non-linked game he has never seen him before.

In Labrynna he builds his Moblin Keep (with warning signs all around it) and rules over the mountain and its inhabitants, preventing the Gorons from growing their famous Bomb Flowers—he makes the more traditional sort of bombs (by hand), so it is to be assumed that he wants to drive them out of business.

In Holodrum he builds another Moblin keep, but this one is very different and has cannons all around the walls. He stands on the wall shelling anyone who comes near. However his cannons fire bombs rather than cannonballs, so he is more an annoyance to Link rather than a real threat.

The Great Moblin and his henchmen are greedy, and always out to make a profit. In Holodrum (depending on the story strand) the player will find his minions surrounding Dimitri. They intend to sell him ("Bwee! I found somethin' weird! If we catch it and sell it, we'll be rich!!! And the Great Moblin will be very pleased!!!"). If Link wants to rescue Dimitri from this fate he has to pay them a total of 80 Rupees in exchange for him.

If the player is in Holodrum while playing a linked game, the Great Moblin kidnaps Princess Zelda, once again hoping to make a profit ("Such fine clothes... You must be a high-class girl! Rupees, jewels, everything! Give me your valuables!"). After a brief skirmish he flees back to the Moblin Keep.

After Link destroys the Holodrum Moblin Keep, he will not leave the land (like he does when his Keep in Labrynna is destroyed) but will instead move into an abandoned house in the south-eastern corner of Sunken City. There he and his minions make bombs, apparently to sell to get the funds to rebuild his Keep once more. If Link drops a bomb or an Ember Seed on this pile and then runs out the door, the house explodes, and the Great Moblin and his henchmen flee the smoldering ruins. However they soon return and rebuild the house (in a much shabbier state), and continue making bombs once more. Link can blow up this second house too, and they will flee yet again. The next time they rebuild, however, the moment Link ignites their pile of bombs the Great Moblin says, "Bwee-hee! So it was you! You'll pay!!! An eye for an eye!". They throw Link into the house and run away, and it explodes with him in it, killing him (and giving the player the save/continue menu as with any death).

Moblin Ring
In both games, the player can acquire a magical Ring that transforms Link into a Moblin. He cannot use any attacks in this form, but he is ignored by any Moblins (with the exception of the Great Moblin), and also cannot be eaten by Like Likes. Can only be found in the possession of Maple, or inside of a Gasha Nut.

Wind Waker
In The Wind Waker, Moblins wear Skull Necklaces, items which Link can later sell for quite a nice price. They carry lanterns, and attack using Moblin Spears.

We can tell that Moblins are not totally heartless from Moe's relationship with Maggie in The Wind Waker. Suggesting the Moblin race may not totally be evil.