If you use Flash to move a unit targeted by Hidden Blade back to base, does the controller still draw 2 cards?

Ruling: No, if you Flash a unit in response to Hidden Blade, the controller does not draw 2 cards. When Hidden Blade resolves, the unit is no longer at the battlefield, making the target illegal and preventing Hidden Blade from determining "its controller."

Sequence:

• Player A plays Hidden Blade targeting a unit
• Player B responds with Flash, which resolves first
• The unit moves back to base
• Hidden Blade resolves but cannot find the target at the battlefield, so "its controller" becomes null and no cards are drawn

Nuances:

• Death prevention abilities like Zhonya's work differently - they allow you to draw 2 and save the unit because Hidden Blade begins resolving and identifies the controller before the unit is moved
• The key difference is timing: Flash moves the unit before Hidden Blade resolves, while Zhonya's triggers after Hidden Blade starts resolving and can identify the controller