Title card's issue homage: The Incredible Hulk #1.
When Klaw falls to the ground and later when the Hulk bashes him into the ground, he shouts 'Feyenoord' and possibly 'Ajax', the names of two Dutch soccer teams. The character of Klaw is originally from the Netherlands.
When Thor zaps Toad with lightning Silver Surfer says "So that's what happens when a Toad is stuck by lightning." Which is a reference to the the first live action X-Men movie (2000) when Storm asked Toad "Do you know what happens to a Toad, when it's struck by lightning?" Before zapping him.