Siskel & Ebert is a competitive UR Commander deck. It uses Krark’s triggered ability to win through storm lines. This is an adaptive deck that can pivot quickly between storming off and playing control. It supports win attempts on turns 2–5, usually winning on turn 4.
Siskel & Ebert’s main engine is formed by cloning Krark and/or adding Krark triggers. Sakashima’s Mirror Gallery effect allows you to make non-Legendary copies of Krark. Cards like Harmonic Prodigy and Veyran, Voice of Duality give you additional Krark triggers. Krark’s Thumb increases your odds of flipping desired outcomes. These effects support each other, enabling you to copy and return to your hand instants and sorceries—thus enabling you to use them over and over and over again.

This deck’s main engine turns low-cost rituals (like Rite of Flame) and cantrips (like Gitaxian Probe) into game-winning sources of card draw and mana. This deck features synergistic and layered win conditions. This is a proactive deck that plays a strong control game. As shown by its excellent tournament records, this deck can adapt to most metas. Lastly, this deck creates stacks with hidden information against which it is impossible to play optimally; this opacity is unique among cEDH decks.
Key Points

This deck can attempt early all-in wins.
This deck struggles against explosive stax.
This deck’s main engine relies on its commanders.
This deck has many interlocking paths to victory.
This deck is non-deterministic; you can get unlucky.
This deck features many value engines that are hard to effectively disrupt.
This deck requires close attention to storm counts and floating mana.
This deck runs Krark’s Thumb. Competitively.

Underworld Breach + Brain Freeze + Lion’s Eye Diamond/Lotus Petal/rituals = mill out your opponents
a creature + Twinflame/Heat Shimmer + Dualcaster Mage = infinite Dualcaster Mages with haste
≥2 Krark triggers + Dockside Extortionist/Storm-Kiln Artist/Tavern Scoundrel + Twinflame/Heat Shimmer = infinite creatures with haste
≥2 Krark triggers + Grapeshot/Lightning Bolt/Brain Freeze = lethal direct damage or mill
≥2 Krark triggers + Veyran, Voice of Duality/Storm-Kiln Artist/Harmonic Prodigy = big attackers