That was my reaction too, 20,000 (euros) seems quite decent for a tiny freelance engagement, and just skimming the contract, that all seems bog-standard, too.

If he didn't think the money was fair, he shouldn't have accepted it. I expect Mojang would have simply pulled the plug and gone with someone else if he had done so.

This really just smacks of sour grapes that Mojang was sold for squillions and the author feels entitled to some of that. Legalities aside (the absence of aa signed contract may be a problem) but I don't feel he is morally entitled to anything more than he's already received.

reminds me recently of voice actors who think they are entitled for a bigger piece of the piece just because the game they worked on for a few hours had financial success. Hubris and pretentiousness at its best.

The problem with that line of thinking is that Minecraft itself is not worth $2.5 Billion of programmer's time under the same type of analysis.

The ending is like the smile on Mona Lisa in my opinion. You can probably pay someone a few hundred dollars to paint that smile ...