[quote=@King Cosmos]
<Snipped quote by Deluge>

I haven't played Yu-Gi-Oh or even followed it for a couple years now; I stopped back when the first Kozmo cards were first being released. I don't know what the current meta looks like but the Lair of Darkness deck does look interesting and very strong. A field spell that makes it so that you can tribute your opponents monsters, something that nothing really has a defense against except this decks boss monster, for their own effects is crazy.

Plus, if I am reading the effects right, the fact that you can tribute a dark monster you control to search the boss dragon, then immediately summon that dragon because you tributed a dark monster this turn, because the boss does not have to have been in your hand when the tribute was made to be able to activate the self summon effect.

I can see the field card being limited if this deck does well and maybe the search monster as well.
[/quote]

Lair of Darkness is a pretty good field spell, as with the tribute effect of Diabolos it basically becomes a potential hand-loop /w Kaiju tribute effect stacked on top of it. The single token isn't a big disadvantage to use the tribute effect on your opponent's turn anyways,and on your turn you get a free token for potentially nuking one monster your opponent has, while also making them put a card back in the deck. Even while down to 1 this card could be really good.

Diabolos is just -super- easy to get out. That being said, it's not the be-all end all boss monster. Ultimate Conductor Tyranno is even easier to summon and easily outs Diabolos by either flat-out destroying it in battle or by flipping it (As U.C.T doesn't target with it's flip effect) Though in return if Lair is active then Diabolos can just tribute U.C.T. and call it a day. Though Dinos can combo heavily, so they'll possibly already bait out your effect or use U.C.T as bait for it then make extensive plays. 

It'l require some testing though it's looking strong for this year. Pend magicians are getting hit hard, so along with Zefra and Dinos this deck could get high in the tiers with some tinkering. Curious to see the plays people think of.