Start with the amount of damage being dealt to the creature and determine what is "lethal." This is usually the creature's toughness minus the amount of damage that it already has marked on it, but ignoring any replacement or prevention effects that will modify this damage
Although, is that your toe sticking out from under the covers
Secret Door It may surprise you, but Secret Door is one of the best mana sinks and win conditions you can have when you get access to infinite blue mana, as you can endlessly go through all dungeons and win with it
As always feel free to respond in the comments below to anything discussed in the article above, especially if you feel I might have missed something important, or gotten something wrong
Group hug is a lot of fun when played responsibly, at least in casual settings
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