Yet again it's
a cat.
Stop worshipping me!
Away! you flea!
The cat is telling us, the riddlers of Stackexchange, to stop writing riddles about it :-p Also, in former times, Egyptians worshipped cats. Cats get and surely hate fleas :D
I'll stomp you with my boots,
This is a reference to Puss in Boots.
You know I'll accept any substitutes,
Cats are not known for loyalty.
At first, I change you,
Then I begin to arrange you,
And finally I end your precious heartbeat!
C is the first letter in change; then the letter A begins the word arrange, and finally the letter T ends the word heartbeat - spelling out CAT.
The title is also a hint, since two riddles with similar titles have both had the same solution.