Obstacle is the opposite of Benefit. Benefit is related to Gain. Gain is a synonym of Derive. 
one thing you do when you Surprise is Laugh. Laugh is related to Expression. Clothes can be used for Expression. Clothes is related to Hook. 
Obstacle <--Antonym--> Benefit <--RelatedTo--> Gain <--Synonym--> Derive 
Surprise --HasSubevent--> Laugh <--RelatedTo--> Expression <--UsedFor-- Clothes <--RelatedTo--> Hook 