If you sacrifice a buffed unit with Baited Hook, can you hold Vanguard Helm's effect until after Hook finishes resolving to buff the unit you just played from Hook?

Ruling: No, you cannot buff the unit played from Baited Hook with Vanguard Helm. When Hook kills the buffed unit, Helm's trigger is added to the pending chain first, then the unit from Hook is added to the pending chain second. Pending items are finalized in the order they were added (first in, first out), so Helm finalizes and requires a target before the Hook unit is played.

Sequence:

• Baited Hook resolves and kills a buffed unit
• Vanguard Helm's trigger is added to the pending chain
• Hook continues resolving: look through top 5 cards, banish the chosen unit, add it to the pending chain as a pending item
• Hook finishes resolving and is recycled
• Finalize Helm (choose targets - the Hook unit is not yet played, so cannot be chosen)
• Finalize the unit from Hook (the unit is now played)
• Resolve the unit's "when you play" triggers (if any)
• Resolve Helm's buff effect

Nuances:

• Nothing goes onto the resolve chain during resolution, only the pending chain
• Pending items are finalized in the order they were added (first in, first out)
• The resolve chain itself works last in, first out
• You cannot play a card while an ability is resolving, which is why the Hook unit must be added as a pending item first