MTG & Commander rules, explained
Rules guides for the stuff that ends up on your life counter. Commander damage, poison, the monarch, counters, and how much life every format starts with. Short answers first, edge cases after.
MechanicsThe Ring tempts you: how the Ring and your Ring-bearer work
Each time the Ring tempts you, you choose a Ring-bearer and your Ring emblem gets stronger, up to four abilities. Here's every level and the rules people get wrong.
CommanderCommander damage: how 21 works
Take 21 combat damage from one commander and you lose, no matter your life total. Here's what counts, what doesn't, and how partners, copies and infect change things.
CountersPoison counters, infect and toxic
Ten poison counters and you lose, whatever your life total. How infect, toxic and proliferate hand them out, and what changes in Commander and Two-Headed Giant.
MechanicsThe monarch vs the initiative
The monarch draws an extra card every end step until someone hits them in combat. Here are the exact rules, what happens when the monarch leaves, and how it compares to the initiative.
MechanicsThe initiative, explained
Take the initiative and you venture into Undercity right away, then again every upkeep. Here's how it works, how to steal it, and what happens if you're already in another dungeon.
CountersRad counters, explained
Rad counters mill you at the start of your precombat main phase and drain 1 life per nonland card. Here's exactly how they work, how they go away, and how they combine with proliferate.
CommanderCommander tax, explained
Each time you cast your commander from the command zone it costs 
more. Here's how commander tax adds up, when it doesn't apply, and the cards that get around it.
FormatsStarting life in every format
20 in most formats, 40 in Commander, 25 or 30 in Brawl, 30 shared in Two-Headed Giant. The full list of starting life totals, plus commander damage and poison for each format.
CountersProliferate, explained
Proliferate adds one more of each kind of counter to any permanents and players you pick. How it works, what you can and can't proliferate, and the tricks Commander players use it for.