I don't think that's a contract. We need an offer and acceptance (and consideration). More broadly we also need adequate specificity to determine the essential terms.
Here there were two essential terms: 1) the author would write a poem for use in Minecraft, and 2) Minecraft would pay consideration.
Stepping through the rounds:
1. ... skip prior rounds ...
2. Minecraft demands that Julian accept Minecraft's first offer. [This is not an offer because it does not specify the essential term, consideration.]
3. Julian agrees to accept Minecraft's first offer. [This is also not an offer, because they still have not indicated what the consideration will be.]
4. Minecraft offers $20,0000 in exchange for the poem. [This is the first offer.]
5. Julian refuses to sign. [This is a rejection of the offer.]
I don't think that's a contract. We need an offer and acceptance (and consideration). More broadly we also need adequate specificity to determine the essential terms.
Here there were two essential terms: 1) the author would write a poem for use in Minecraft, and 2) Minecraft would pay consideration.
Stepping through the rounds:
1. ... skip prior rounds ... 2. Minecraft demands that Julian accept Minecraft's first offer. [This is not an offer because it does not specify the essential term, consideration.] 3. Julian agrees to accept Minecraft's first offer. [This is also not an offer, because they still have not indicated what the consideration will be.] 4. Minecraft offers $20,0000 in exchange for the poem. [This is the first offer.] 5. Julian refuses to sign. [This is a rejection of the offer.]