There's an integer n>0 such that subtracting n (where A=1, …, and Z=26) from some (more than one) of the letters in word #1 yields word #2.
Replacing the first plosive in word #3 by a fricative and the first vowel by a syllabic approximant yields word #5.
Replacing thunder with war in word #5 yields word #4.
In America, replacing what sounds like a plural in word #3 with what sounds like a comparative yields word #7.
What's word #6?