Agent of the Iron Throne (CLB) cant be used as a background in the command zone here but it is still excellent in the 99 given that you have two commanders and are likely to have one in play to bleed the table whenever you sac artifacts
Really, you should be playing at least Reality Shift, Rapid Hybridization and Pongify in any mono blue deck
That being said, in decks like Atraxa, Praetor's VoiceAtraxa, Praetor's Voice, Pir, Imaginative RascalPir, Imaginative Rascal, Vorel of the Hull CladeVorel of the Hull Clade, or other Proliferate decks, this is another option to go alongside Astral CornucopiaAstral Cornucopia, Everflowing ChaliceEverflowing Chalice, and Pyramid of the PantheonPyramid of the Pantheon
This adds Red to the counter loving Simic, so you get more options, and then you get a nice size beater that grows bigger as it's answered, costing a massive six mana is a rough ask
Caelorna, Coral Tyrant The amount of toughness matter cards really helps strengthen the position of Caelorna, Coral Tyrant and could cause it to rise in value in the future
These decks are already pricey at MSRP ($70), but still probably worth it at that price
