So to celebrate St. Patricks day this year I decided to watch all 8 Leprechaun movies (each one for the first time, incidentally), and did so over the course of 3 days. While they're still somewhat fresh in my mind I wanted to document all of the "lore" from the franchise and how it changes from sequel to sequel because... um... well I don't really know. Fun?

Leprechaun (1993)

• Four leaf clovers repel and can harm the Leprechaun (think crosses and vampires). If he eats one he'll explode.
• Trapping the Leprechaun in a box and putting a four leaf clover on top of it will make it so the Leprechaun can't escape until the clover is removed.
• The Leprechaun bites at least one person with no ill effect other than a bite wound (this becomes pertinent in a later sequel).
• Possessing the Leprechaun's gold essentially marks you for death as he will take it back and kill you as revenge for having it in the first place (also becomes pertinent later).
• The Leprechaun is a cobbler by trade and can't resist the urge to shine dirty shoes (so throwing dirty shoes at him can be used as an effective distraction technique).
• If you leave tiny vehicles or other cute methods of transportation around the Leprechaun will use them and it will be amazing.

Leprechaun 2 (1994)

• Contrary to what was pretty firmly established in the first movie, now if you have a piece of the Leprechaun's gold he can attack you but you can't actually be hurt or killed by him.
• The Leprechaun can be hurt by weapons, or trapped within containers made of wrought iron (it glows red like it's burning him when he comes into contact with it).
• If you trap the Leprechaun he has to grant you three wishes, but it's like monkey's paw on steroids. (It's not actually clear to me whether this is true, or if the Leprechaun was just bluffing and playing along with the idea in order to escape. He does "grant" some wishes but basically just used his powers to turn the wishes against his captor.)
• No mention of four leaf clovers in this one.

Leprechaun 3 (1995)

• This is the first appearance of an unexplained gold medallion that will imprison the Leprechaun by turning him into a statue when placed around his neck.
• Each piece of the Leprechaun's gold now grants its holder one wish, but if you lose possession of that gold piece the wish will backfire (typically resulting in death).
• It's not clear whether posession of the gold still protects you at all. There's no specific mention of it, but I think in all of the kills the person being killed has already somehow lost possession of the gold piece that granted them a wish.
• In this one if the Leprechaun bites you, you slowly begin turning into another Leprechaun (think werewolves). This is the only sequel in which this is a thing, it's never brought up again (even though I'm pretty sure the Leprechaun bites more people).
• Leprechauns are extremely territorial and will fight other Leprechauns if they come across them, even if one of the Leprechauns was created via a bite from the other one.
• To kill the Leprechaun you must destroy all of his gold.
• No mention of four leaf clovers in this one that I can remember.

Leprechaun 4: In Space (1997)

• The Leprechaun may be an alien? At least he has knowledge of and interactions with other alien races in the galaxy (but humans do too at this point, so it's not really clear whether the Leprechaun was already involved in galactic affairs prior to whenever humans made contact).
• No mention of clovers, shoes, wishes, the medallion, bites, or for that matter (I think) the Leprechaun's gold at all that I can remember. In fact I don't think anyone even says the word "Leprechaun" throughout the entire movie.
• The Leprechaun can transfer himself into your body via your urine if you pee on him (or a chunk of him).

Leprechaun in the Hood (2000)

• The medallion that can turn the Leprechaun into a statue is back in this one.
• The Leprechaun possesses a magical flute that makes everyone who hears it blindly follow and adore the person who played it (think pied piper). Once its effects wear off the listeners have no memory of anything that happened while they were under its spell.
• If the Leprechaun smokes weed laced with four leaf clovers he'll lose his powers and/or pass out for a while.
• The Leprechaun has the ability to summon "zombie fly girls" from hell who will assist him in fighting and/or escaping from people who stole his gold or trapped him, and also act as backup dancers when he's performing rap numbers. The final sequence actually confuses this a bit, as it shows him turning normal girls into the zombie fly girls by touching them, so it's unclear to me if he actually ever summoned anything from hell or not.
• As mentioned, in this one the Leprechaun has the ability to mind-control or possess humans by touching them (you can tell when someone is possessed because their eyes glow green).
• No mention of wishes in this one.

Leprechaun: Back 2 Tha Hood (2003)

• Splashing the Leprechaun with holy water laced with four leaf clovers can summon demons that will drag him back to hell (maybe only if you're a priest though). The Leprechaun will only be released from hell if someone finds and takes his gold from wherever he stashed it.
• In previous films the Leprechaun's gold was always represented by a pot that typically had exactly 100 gold pieces in it (counting it is how the Leprechaun would know someone still has some of his gold). In this one that's been replaced by a small wooden chest that contains essentially unlimited gold pieces because it magically refills itself whenever closed.
• This is the first one where I don't think the Leprechaun uses any magical powers at all, instead relying purely on physical attacks (except maybe when fighting the witch, I forget now).
• Shooting the Leprechaun with bullets containing four leaf clovers will hurt him, but not very much.
• Oh yeah, and witches (or at least humans with magical powers) are real too now, but not really powerful enough to effectively fight the Leprechaun.

Leprechaun: Origins (2014)

• The Leprechaun isn't even a Leprechaun anymore, they're more like those things from the cave in The Descent.
• The Leprechaun(s) will feed on villagers unless they satiate him/them with occasional human sacrifices.
• The less said about this one the better.

Leprechaun Returns (2018)

• This is the kickoff of the Leprechaun Multiverse because it's a direct sequel to the first movie, erasing all the other ones from history (except possibly Leprechaun 4: In Space, since that one occurs in the distant future).
• Four leaf clovers can hurt the Leprechaun again. He'll explode if he eats them again.
• The Leprechaun's compulsion to shine dirty shoes is a thing again. To be fair this did come up in some of the other movies too, but only as a gag and never really utilized as a distraction like this since the first movie.
• I think wrought iron was mentioned again, but I don't recall it actually being used.
• The Leprechaun's gold is exactly 100 pieces in a pot again.
• If you leave things that he can ride laying around he'll do that again too.
• Ghosts are real.
• The Leprechaun can transfer himself into your body if he can get some of himself into your mouth. I think this is the only time some new lore established in Leprechaun 4: In Space makes an appearance in another movie.

I'm sure I forgot some things (or possibly even got some wrong), but I find it interesting and entertaining that it seems like other than "the Leprechaun likes his gold and will kill you to get it" there isn't really a single "rule" that sticks across every movie in the franchise (even if you exclude Origins, which basically isn't even a Leprechaun movie at all).