In "King Geoff: Part 1", episode 57 of Let's Play Minecraft, Michael asks whether Geoff is more like Robert Baratheon or Joffrey. He hopes he's like Robert, but offhandedly suggests that maybe he's more like the Mad King. Now, who was it that placed all that TNT underneath Achievement City, again? This, of course, raises the question of who the Kingslayer will be. Your move, WMG.
In episode 65 of Let's Play Minecraft, Gavin breaks into Ryan's house, kills Edgar, and replaces him with a Mooshroom before escaping. Later, Michael enters and plants a sign referencing Free Edgar 2013. You'd think he'd be confused about Edgar becoming a Mooshroom, since Gavin said nothing about doing such and Michael didn't see. Then you remember back when Michael first freed Edgar in the King Ryan episode; he and Gavin had a quiet conversation that implied that Gavin saw what he did. He and Gavin are working together to free Edgar (or at least screw around with Ryan), so either they planned before the let's play for Gavin to replace him with a Mooshroom, or when Michael walked in and saw the Mooshroom he already knew that was Gavin.
All the houses in Achievement City actually have some form of irony to them that matches up with whoever owns the house:
Michael, theSir Swearsalot, has a censored sign on the front of his house. He also has the most normal house out of the bunch, despite being far from the Only Sane Man.
Jack, usually the most calm and least likely to screw with the others, has a house that frequently causes trouble for the others (particularly Geoff and Gavin), either by catching fire constantly or being the hardest part of building Dark Achievement City.
Generally considered to be the least egotistical and competitive of the group, he also has behind his house a giant statue of himself with a six meter long dick.
Ryan's house is the apparently inescapable prison for Edgar, even though from the outside it looks moderately normal and is made out of dirt.
Come episodes 217 to 219, everybody else deliberately employs this irony to relocate Ryan's home to the bottom of a deep hole, thus doing to him what he did to Edgar.
Geoff's gigantic house is the only exception to this. However, as he rarely wins the Tower of Pimps due to being the game master most of the time, it could count as he almost never wins yet has the biggest home of them all.
It should also be noted that Geoff and Gavin, the usual game masters, both have stone houses (though Gavin's is cobblestone) while Ray and Ryan, "The R and R Connection" and most likely to be The Ace, have dirt houses. Jack and Michael both have wooden houses, but aside from them both being the most likely to get annoyed with Gavin, there isn't much of a connection between the two of them.
And as of Episode 154, they have a beautiful house that everyone put a lot of effort into... with nobody living in it at first. Now it's owned by Jeremy, who wears a scruffy Castaway skin.
Obviously the G in "Plan G", also known as the TNT under Achievement City, was planned to stand for Geoff and Gavin (it's certainly their team name), but it could also stand for grief; in Minecraft, "griefing" is when someone destroys another person's work for no reason other than his or her own amusement. Sounds pretty accurate to what Geoff and Gavin did with the lava in Jack's house and all that TNT.
Similarly, looking back on that episode, it's hard to get why the two of them went through all that trouble to prank Jack, considering that the main Butt Monkeys of Achievement Hunter are Gavin and Ray. Then you remember that this whole thing was (presumably) Geoff's idea, and he and Jack have a very consistent Vitriolic Best Buds relationship, even if it doesn't show up in Minecraft that much.
Except for Michael's (until Episode 89, see below), everyone's house in Achievement City has had some sort of expansion to it. Geoff has the circuitry for Indoor Pool; Ray has the circuitry for Cake Wall; Gavin has his "Trophie" Room; Jack has the statue of himself that doubles as a fire extinguisher; and Ryan has Edgar's hole. The fact that Michael's house has been exempt from this rule makes sense when you realize that the position it is in doesn't leave a lot of room for stuff to be added, and he hasn't wanted to use his house for much aside from a spot to sleep. So naturally he wouldn't want to add much to it, and Geoff and Gavin don't really have anything to put in for a Let's Build.
As of Episode 89, Michael's house does have something added onto it - Kerry's bedroom is underneath it. This fits in with the logic above, as even the addition to Michael's house is a place to sleep.
A couple episodes later, it's revealed that Gavin and Michael have connected their houses underground with a new trophy hall for Team Nice Dynamite, so Michael now has something more than a place to sleep.
When the guys switch to PC Minecraft rather than Xbox for Galacticraft, people might notice Gavin becoming more competent and Michael less so - to quote a comment: "Gavin's doing vital business while Micheal [sic] does creepy faffing... is it opposite day?". Gavin played a lot of PC Minecraft back before the guys even did Minecraft let's plays, so he's used to it; plus, the Galacticraft let's plays aren't challenge-oriented, so it's basically survival and crafting like regular Minecraft. Meanwhile, Michael had enough trouble learning Xbox Minecraft (and jury's still out on whether or not he even has learned it), so now that he's in a mod, he's back to square one with no idea how to do things. It suddenly makes sense why Ryan gave Gavin actual things to do, yet just sent Michael away to gather food.
Something very similar happens in the Sky Factory series: Michael struggles to find a niche because he's got no idea what he's doing or how anything works. He does eventually find a role with the Botania mod, but only after Jeremy brought him into it. Lindsay also suffers from this issue because she's only in the series occasionally, so she has less equipment and idea of how to do things.
"Edgar"'s inclusion as the final boss in Mad King Ryan provided us not only with a twist to the whole two-parter video, but as Ryan later notes in Episode 109 - it makes Edgar technically part of a previous Let's Play. He's now off-limits from being killed for future ones!
There are various (unintended) connections between Dig Down and Mega Dig, which is fitting considering Mega Dig is "Dig Down X" in all but name.
Both of them were two-parters.
Both let's plays were plagued by all sorts of technical issues. Geoff lampshades this.
Both let's plays had deaths primarily by lava (well, Mega Dig had more silverfish deaths, but those weren't around during Dig Down).
Throughout the course of both let's plays, the participants slowly went through Sanity Slippage.
And lastly, Jack won both let's plays. Again lampshaded by Geoff.
Gavin's tower (him specifically) in Achievement Highlands had multiple silverfish blocks in the build design, meaning it'd destroy itself and spawn mobs if someone tried to sabotage it. This may seem like it's part of his Butt-Monkey status, but it isn't purely that. Gavin is a notorious minecraft troll, and one of his early Things To Do In Minecraft videos is replacing an entire stone house with silverfish blocks. Who else but Gavin would have silverfish trolling as a defense mechanism?
Jack 'the house guy' is the last person to build their house in Achieveland. However it makes sense when you realize Jack originally would build houses when he gives up trying the main focus of the episode. In Achieveland, Jack's too into the event to build a house!
The identity of the Christmas King. Of course Jack isn't the big fat jolly bearded guy. That would be too obvious.
Ryan constantly insists that Edgar is not being trapped, and that he's free to leave whenever he wants. Turns out this is true... because Ryan will just go get a new Edgar to take his place.
Minecraft has phased out red roses in favor of "red poppies". What will Ray do once the console versions update?!
Ray's Deadpan Snarker mentioning of this update (quoting the tons of people asking by muttering "Hey, someone tell Ray that roses are being taken out in the next update") implies that he doesn't really care. Plus, since there are rose bushes, he'll probably just switch to those.
Ryan has said that no matter what, "Edgar is the one in the hole". That said, the solution to free Edgar is blatantly obvious, yet nobody has done it... why has nobody gotten rid of the hole? Preferably by filling it with Obsidian? Or, in an extreme case, sneaking in in creative mode and filling it with Bedrock?
Because unless the hole is filled with bedrock, Ryan can just break the blocks to make the hole again (even if it would take a while). And bedrock is highly unlikely since Geoff, Gavin, and occasionally Ryan himself are the only ones who go onto Achievement City in creative mode, and that's only for building challenges; Geoff seems to be pretty indifferent towards the whole Edgar thing, and while Gavin may attempt such a thing for the sake of trolling, he'd probably be forced to undo it or Ryan would make a loophole. Plus, Ryan could just turn around and say that the blocks used to fill the hole are Edgar, since they are in the hole.