Don't Starve: Giant Edition

To unlock WX-78 you need to survive 48 days. You will unlock him on death or transporting through a portal once you've survived the required amount of days.

WX-78's unique features are:

• He can eat spoiled food without issue.
• He is damaged by rain but if struck by lightning he goes into overdrive mode which cause him to regain his health, move extremely fast for the duration and emit light in an area comparable to a torch.
• He can eat gears which permanently upgrade all his stats, reaching the limits after eating 15 gears. Even after that though you can continue to eat gears to restore a massive amount of health/sanity/hunger.

The gears are the main reason I feel WX-78 is the best character for adventure mode, while the first area can be difficult, once you reach the first clockwork monsters and get a stack of gears you should be fine. You can hold on to these through every world, I ended up with a full stack of 40 for the final world. Basically you shouldn't have to worry about hunger/sanity for the rest of the playthrough and his max upgraded health of 400 is a lot higher than other characters.