A few thoughts on some of the card choices...
Snowl: Not only is the book of moon effect a strong disruption, but the additional summons allow us to play under Monarchs Erupt without issue since it negates our small birds on field effects but not their recycling effects.
2x Mega Raiza: Running two protects from an unlucky banish/mill and allows us to loop them off each other. This is even easier with the discount from Domain of the True Monarchs.
Gold Sarcophagus: Extra consistency since we can’t play Pot of Prosperity. This is could be a flex spot but I’m hesitant to cut it.
March of the Monarchs: The protection is nice but it’s primarily here for its synergy with Pantheism of the Monarchs. I wanted more Monarch spell/traps for the discard and it’s another name that can be used for Pantheism’s graveyard effect as well.
Ash Blossom and Infinite Impermanence: These are flex spots and can be changed to whatever hand trap best fits the current meta game. These were chosen because they’re generally live against most decks even if they aren’t the most impactful hand traps.
Side deck: I’m pretty unsure about the side deck. I tried Monarch Stormforth for additional Pantheism targets but ultimately I like Unexplored Winds more. Cosmic Cyclone and Dark Ruler No More are for going first and second respectively against Superheavy Samurai. I’m not sure how to best side against Purrely.
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