Solemn Judgement/Solemn Warning

I have a question....when I play Polymerization, and the opponent has Solemn Judgement/Warning, can they activate the trap after I summon the fusion monster? Or, do they have to chain Poly in order to negate it? Thanks in advance.

Your opponent would have to chain Solemn Judgment or Solemn Warning to Polymerization's activation. If they let Polymerization resolve and the Fusion Monster comes out, they have missed their chance to stop the Fusion Summon.

Yes thats the easyest way to explain it
Just Remember warning/Sollem cant negate summons caused by other cards
and youll do fine

V--- What he said they still can negate the Cause (unless its Fusiongate/Super poly)

But you can warning the card that would special summon another card