If the top card of your library is a historic card with a disguise or morph ability, you can't cast it face down from the top of your library with the permission granted by Crystal Skull because the resulting spell would not be a historic spell
You can build more controlling decks, leaning on whites excellent removal and cards like Goblin Rabblemaster and Goldspan Dragon to close the game
Legality depends on the tournament format -- Fire Covenant can be legal in some formats and banned or restricted in others
Definitely sit on any variant art Guardian Projects you pull
Paul was presented with his official Guinness World Records certificate after his WWE debut, in which he fought a tag team match with The Miz against The Mysterios, eventually coming out on top
for Rorix, it is the understanding that, just because you sideboard something in for nearly every matchup, it doesnt mean the card belongs in the maindeck