Mox Ruby is free to play with a 0 casting cost. Tap that (turn it sideways) to add 1 mountain (red mana: ๐) to your mana pool. You don't remove it from the board.
You have ๐ in your mana pool. 1 total mana.
Black Lotus is free to play with a 0 casting cost. You can turn it sideways, remove it from the board into your graveyard pile, and add 3 of any color to your mana pool. Choose green for forests: ๐ฒ๐ฒ๐ฒ.
You now have 4 total mana: ๐ ๐ฒ ๐ฒ ๐ฒ
Channel costs ๐ฒ๐ฒ. Cast that, remove ๐ฒ ๐ฒ from the mana pool, and pay 19 of your 20 starting life, so that you gain 19 colorless mana (can be used for most spells). Place Channel into the graveyard pile.
Your mana pool will now have a total of 21 mana: ๐ ๐ฒ + 19 colorless
Fireball costs ๐ + any amount of mana you decide, up to how much you have available. So you then use your remaining ๐ฒ+ 19 to do 20 damage to your opponent.
With those four cards you can turn 1 kill. Magic typically starts with each player at 20 life. Black lotus adds three green mana. Channel costs two, but lets you pay one life to add one generic mana as many times as you want. Mox ruby pays for the red in fireball. Pay 19 life for 19 mana, with the last green you have 20 extra mana to invest into fireball, dealing 20 damage to your opponent and ending the game.
If you draw this hand, your opponent has zero ways to respond, and the game is no longer fun.
Of course, that's the joke. The only winning move is not to play.
There is a meta-joke in that there are a few ways to respond to this, but only if you know it's coming. @[email protected] responded with one. If your opponent also has a way to get fast mana out, a simple Lightning Bolt will also do it if it's inserted between your Channel and Fireball. Or anything that counters your fireball, which will leave you standing there with your pants down around your ankles, 1 life, and probably an empty hand.
Then the meta-meta-joke is if you are known to be packing this combo, people around you will deliberately structure their decks around countering your stupid 1 turn win (if they will even allow you to employ it at all, given that Black Lotus is very, thoroughly, extremely banned specifically because of this combo), but this requires making sacrifices to their usual strategy and then you can show up unannounced with a different deck instead...
Black lotus and mox ruby have zero mana cost, play those. Use the black lotus to give you two green and one of your choice to pay for channel, sacrifice 19 life to add 19 mana to your manapool. Use the mix ruby to pay the red mana cost for fireball and then use the 20 mana in your manapool as the x cost, make opponent take 20 damage and you're done.
Unless it's changed, artifacts dont suffer from summoning sickness so you can use the tap abilities out the gate.
There's some counters like Foil, Force of Will that I think could work or Misdirection. Can't recall if there's any instants that do damage that you can discard or exile cards from your hand instead of paying for because that could work too as fireball is a sorcery (if I recall how the stack works correctly)
Correct, any instant (or interrupt, if you have cards from expansions old enough to still have them) will work. Fireball is a sorcery and is slower, so instants/interrupts will resolve first.
You also have the potential to be scooped if you do not win the coin toss and don't get the first turn. There are tons of single cost interrupts and various fast tweaky creatures that can deal small amounts of damage on the first turn, and all your opponent has to do is shave off one single point of life from you and this won't work.
This is a wild turn one combo that will win if both players have the same starting life. Assume 20 life each, you play the first card to give you 3 green mana, you play the second card using 2 green mana. This card let's you use 19 of your life for mana leaving you at 1 life and 19 manager + 1 from the previous card. You play the third card which gives you one red mana (totals are 20 green, 1 red) and finally now you can use the last card by paying one red and X (X can be any number you choose as long as you can pay it). In this case X is going to be 20, for the 20 green you had dealing a perfect 20 damage to the other player leaving them at 0 life and yourself at 1 life.
This combo works for whatever life total as long as yours is greater than or equal to Theirs
This is a first turn win if you draw all four of these cards in your opening hand.
Black Lotus and Mox Ruby can be put down on your opening turn, and since they are not lands you are not limited to playing just one of them. If you are poor you can substitute the ruby with a regular old mountain. Basically, I only employ the ruby here to firmly illustrate that I am indeed an asshole.
If you are poor, cheeky, and lucky you can replace the Black Lotus with 3 Lotus Petals and still theoretically draw all the cards you need to do this with your opening hand.
Sacrifice the Black Lotus for 3 green mana.
Spend 2 green manna on the Channel, pay 19 life, gain 19 colorless mana.
Tap the Mox Ruby for 1 red mana.
Use that 1 red mana to cast Fireball. Dump all 19 colorless mana from your Channel, plus the one green left over from the Channel into that fireball.
Fireball does 20 damage to your opponent. You take 19 damage from Channel. You are left at 1 life, but your opponent is dead.
Realistically, just being able to show people this hand will discourage them from engaging you at all in any type of no-holds-barred play. They'll hide behind their silly Modern or Commander formats or whatever, where Black Lotus is banned and Channel is either restricted or banned.