Why bother putting cool cards in your deck when your opponents already have a bunch ready for the taking? Nab 'em and turn them against their former friends.
The general gameplan here is to control the game with your interaction suite while setting up Merieke to start stealin' stuff. On her own, she's pretty fragile, so a lot of the deck can run pretty well without her online. There's a ton of ways to steal or copy your opponents' stuff, between Merieke herself, the numerous creatures that steal stuff like Hostage taker or Gonti, and various perma-steal sorceries/enchantments like good ol' fashioned Control Magic, Acquire, or Scroll of Isildur.
The main notable interaction is between Merieke and ways to untap her. If you suit her up with an enchantment like Freed from the Real or Pemmin's Aura, you can turn Merieke into a little machine gun that can quickly clear out the board of troublesome creatures thanks to her untap clause. There are a few creatures in the list that can also help out with this trick (though just once a turn usually), like Aphetto Alchemist or Ioreth of the Healing House.
You cannot deal with annoying indestructible creatures by stealing them with Merieke and just letter her untap or bouncing her somehow. Her oracle text says "Destroy that creature", so be careful. However, you can deal with stolen indestructible creatures by copying them with Mirage Mirror and sacrificing the original copy to the legend rule.
If you get Cephalid Coliseum online, and have Narset in play, you can use it to just make someone discard 3 cards during their turn after their drawstep. I haven't ever had this come up, but I think it'd be funny.
You can use Mirrormade to copy Auras that are stealing something (like Control Magic or In Bolas' Clutches). You'll get to choose a new target to attach the copied aura to once as it enters.
The deck also has a little bit of a toolbox element to it, with a couple little packages you can search through if you get their enablers. Zur the Enchanter can tutor up 3-mana value or less enchantments, which includes combo pieces like Freed from the Real, control pieces like Blind Obedience, ways to straight up steal stuff like Scroll of Isildur or general card advantage like Phyrexian Arena (though I'm getting to the point where I think just straight up Divination or Sign in Blood might more effective than Arena, but that's for another rant).
Another toolbox is the Wizard creature type, thanks to the wizardcycling on Vedalken Aethermage. You could find Riptide Entrancer to steal a creature (eventually), Zur (to do more toolbox enchantment stuff), Aphetto Alchemist to start the Merieke untap train, and a few other niche options. I'm sure there's a few other wizards out there that'd fit too.
Also, there's a Mystical Tutor in there, so you can dig up most any suitable interaction spell or way to steal something with that too.
I tend to have a lot of fun playing this deck, but with all the board wipes and control options and no strong way to close games out if your opponents don't play out their own threats, games with this deck can be pretty long and grindy, so keep that in mind if its the end of the night and you need to get to bed soon. There are probably a few easy ways to power this down if you wanna play in a lower bracket. I'd drop the chain-untap enchantments and some of the tutors to make the deck less consistent, and maybe lighten up on some of the board wipes to swap them out for more one-off steal effects.
No, there's no particular reason why some of the Islands in here are Snow-Covered. I just like 'em.