Junk Winder is one of those cards players keep asking about. Here is, in plain words, what its official text says, the rulings published by Wizards of the Coast, and the combos players actually run.

Official card text

Affinity for tokens (This spell costs less to cast for each token you control.) Whenever a token you control enters, tap target nonland permanent an opponent controls. It doesn't untap during its controller's next untap step.

Complete guide

Junk Winder is a massive Serpent that rewards players for building wide boards of tokens. By combining a significant cost reduction with a powerful control ability, it can single-handedly lock down an opponent's board. Whether you are generating Treasure, Clues, or creature tokens, this Serpent ensures your path to victory remains clear.

Affinity and Board Control

Junk Winder features two primary mechanics. The first is Affinity for tokens, which reduces the generic mana cost of the spell for every token you control as you cast it. The second is a triggered ability that occurs whenever a token enters the battlefield under your control. This ability targets a nonland permanent an opponent controls, tapping it and preventing it from untapping during that player's next untap step.

Step-by-Step Resolution

First, count your tokens before casting Junk Winder to determine its total cost; it can cost as little as two Blue mana. Once Junk Winder is on the battlefield, any new token entering will trigger its ability. You choose a legal target nonland permanent an opponent controls. Upon resolution, the target is tapped. Even if the permanent was already tapped, the effect still applies the 'freeze' condition, ensuring it will not untap during its controller's next untap step.

Timing and Strategy

Because the ability triggers on any token, including Treasure or Food, you can often trigger Junk Winder at instant speed if you have the right generators. This is most effective during an opponent's beginning of combat phase or end step. A common mistake is forgetting that Junk Winder only targets nonland permanents; you cannot use it to lock down an opponent's lands to prevent them from casting spells.

Interaction examples

Locking Down a Threat

Hullbreaker Horror

If you have Junk Winder on the battlefield and cast a spell that creates a token, Junk Winder's ability triggers. You can target Hullbreaker Horror to tap it and keep it from untapping. While Hullbreaker Horror can return Junk Winder to your hand when a spell is cast, Junk Winder's ability provides a way to neutralize the Horror's presence as an attacker or blocker if a token enters the battlefield.

Controlling the Air

Consecrated Sphinx

When an opponent draws a card and you use Consecrated Sphinx to draw cards, if those draws lead to you creating tokens (such as through another card's effect), Junk Winder will trigger. You can use these triggers to tap down Consecrated Sphinx during the opponent's turn, ensuring that the powerful flyer cannot attack you on their next turn or block on yours.

Token Synergy

If you control five Treasure tokens, Junk Winder costs only two Blue mana to cast. Once it enters, any further Treasure tokens you create will trigger its ability, allowing you to systematically tap down your opponent's artifacts, creatures, or planeswalkers.

Guide written with AI from the official text and rulings. Official English text prevails.