At the beginning of your upkeep, you may put a land card from your hand onto the battlefield
The first is the unlikely scenario that these represent poison counters
Monument to Endurance Excellent value engine Draw, create Treasure, or cost opponents 3 life when you discard a card Can be especially strong if blinked Aetherdrift has quite a few value engines and Monument to Endurance is a pretty great one at just three mana
So, if your opponent deals you damage, they become monarch, and you cast another Azure Fleet Admiral, you get the monarch back
Combine that with Ripple (good luck getting multiple copies), Recover (a very weak mechanic) and Rune Snag cycle, you just don't have a good likelihood of opening something relevant
It is the namesake card of one of the formats most quick and deadly strategies that has been putting up consistent tournament results for over a year now