That calculation was done by using the population (size of the deck), number of successes in the population (amount of mana sources), and the sample size, which is the number of cards youve drawn from the deck by the time you reach the target turn
The Archimandrite is the main incentive for a monk tribal deck in EDH, allowing you to tap monks to draw a card and give them all +X/+0
Each Multiverse traveler card has a set of abilities
The worst-case scenario with the Battle Mammoth is you drop it, someone kills it with Chaos Warp, Path to Exile or Beast Within, and then you draw a card
If you have a playgroup you regularly sit down with, youll know best what to and what not to run in your deck
III You may cast any number of spells from your hand without paying their mana costs