When thunder comes it rains cats and dogs
When gunshots are fired (or the metaphorical thunder), cats and dogs, or his friends, die. It’s a reference to the old saying “It’s raining cats and dogs”, and also demonstrates some wordplay as the TV series ‘ThunderCats’ aired during Kendrick’s youth.
It’s also a metaphor of the saying, “when it rains it pours” (meaning that trouble for dave’s brother just seems to exponentially grow and never get better).
Notice how he distorts “When thunder comes” to sound like the previous “Dun-ta-duns”
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