What is the main strategy to use Disposal Order to break the method to play cards from Discard like Flow or Fizz Ability?

Here's the breakdown of how Disposal Order interacts with each "play from trash" method.

Against Fizz, Trickster (targeted ability): Use Disposal Order reactively. When Fizz's "When you play me" ability goes on the Chain, the target spell is still in the trash — that's your window. Play Disposal Order in response, recycle that specific spell, and when Fizz's ability resolves, the target is gone. The instruction to play it is ignored (Rule 359.3.e.7). The spell never gets played.

Against Flow (alternate cost): You cannot react. Flow spells are played directly from the trash as a game action — the first step of playing them moves them from trash to the Chain immediately (Rule 353). By the time anyone can respond, the card is already on the Chain, not in the trash. Disposal Order only targets cards in trashes, so it can't hit it. The only window is proactive — use Disposal Order during your Main Phase to recycle key Flow spells from their trash before they get to use them.

In short: Disposal Order is a hard counter to Fizz if timed right on the trigger. Against Flow, it's a preemptive tool — clear their trash before they can use it.