Step aside for the B&W guru.
Creature Unlockers: The Creature Unlockers work regardless of version, but you must be on a specific land in order to find the special NPC villager who offers the swap. These lands are 1, and 4. There used to be custom-built sandbox maps that offered this feature, but I can't currently find them. This page offers more detailed instructions:
http://noctalis.com/dis/bw/download3.shtmlAh, okay then.
Back to trying to make him bigger and stronger then, the gist of what I got was "carry rocks around for a while and then sleep in pen"
I assume the pen is the little fenced area infront of the temple gate.
Growing Your Creature: Four easy steps to fast growth:
1. Download this sandbox map:
http://www.kayssplace.com/files/index.php?display=150 (or any eternal-night map)
2. Enter this sandbox, find some blue mushrooms, feed him. Get his hunger down to nil, and fatness around 50%. You can feed him other things to fatten him up, but the mushrooms are special for fast growth.
3. Make him sleep in his pen, ideally at night. Night growth is 50% faster, IIRC. You can edit the sandbox level files (they are .txt) to be eternally night, but it's been so many years, I don't recall offhand exactly where those values are. Should be self-evident.
4. Speed up time and leave him there for a few RL hours. If your map is not eternally nighttime, he will keep waking up, so you will have to actively force him to sleep every time, which is annoying.
KONG Is Bad: Be wary of using Kong. It was the first-ever program created to 'hack' Creature Mindfiles, and has been known to cause problems. Instead, you might want to try Cache's excellent tweaks and utilities. Here is his CreatureStats app:
http://www.kayssplace.com/files/index.php?display=189Casting Food On Self: It is possible to teach a creature to cast Food on himself. Whether he actually eats it is another matter, as he's likely to target something else nearby before the grain pile has 'settled' into a usable state.