It tastes like water. Actually it tastes like nothing but water. Possibly the magic bathtub conjures distilled water to wash with.

Well, if you drink nothing but distilled water in real life you'll get health problems, but maybe that's no more of a risk here and now than smoke inhalation. He'll note other sources of water, but it's not super urgent.

"I'm gonna go exploring, try to find something to eat," he says to the forest spirit. "Wanna come with, or stay here?"

It sways thoughtfully, then declares, {i stay. if you get lost i look for you. careful of time! if lost, build house before dark.}

"Okay." He starts gathering enough wood for a second house. "What will happen just before it gets dark? Will the angle of the light change as the day goes on?"

{late in day, sun goes down, light is different,} the spirit agrees.

"Well at least that's the same," he mutters. "Alright. I'll try to be back before dark and if not I'll be back in the morning. Do you know how long it is until sunset?"

{am not good at time,} it admits.

"That's okay. I'll see you in a few hours or else tomorrow, then."

He sets out in a random direction, making note of his best guess at where the sunlight is coming from and marking his path by hitting the occasional tree exactly once with his wooden axe. After about ten minutes of this, he doubles back to make sure the trees haven't been spontaneously healing themselves as soon as he isn't looking. 

They totally have been.

Fuuuuuuck. That's really cool and he wishes his body could do that, but fuuuuuuck anyhow. He will try dragging a visible track in the ground; does that work? Both in the sense of being able to make the mark with his axe at all and in the sense of it sticking around.

Yes and also yes. Or at least it's not vanishing on the scale of ten minutes.

Great. Now that Bruce has some evidence he isn't going in circles, he goes farther in the random direction. He's looking for any of food, water, the edge of the forest, other nonplant lifeforms, that cave the forest spirit mentioned, or anything else interesting.

And he finds...

...a river!

There's an apple tree growing nearby, covered with large red apples, and a beautiful willow spreading its branches over the water. All the other trees on this side are the same kind that fills the rest of the forest. The apple and the willow share the bizarre regularity of the forest trees but have different branch styles and bark textures.

On the far side of the river—a significant but definitely swimmable span—there's a grassy plain, with tall shoots of bamboo growing amid some more generic tall grasses, and a few towering trees visible in the middle distance.

Wow, stuff that isn't the same trees over and over! 

He attempts to pick and eat an apple. If this is a Bible metaphor he's screwed, but if this is a Bible metaphor he's screwed no matter what and also he's pretty sure the Bible doesn't have any adorable tree-people in it.

The apple is crisp and delicious and does not appear to affect his knowledge of good and evil in any way.

A blob-creature like the green one from earlier comes bobbing around the lazy curve of the river, hopping determinedly against the current. Instead of being a pale grassy green, though, it's divided into six rainbow slices like a jello beach ball.

Once he's down to the core of the apple, he tries burying it a little ways upstream, where it won't be overshadowed by the parent tree if it sprouts. He's very curious about the six-colored slime, but not enough so to grab it and risk exploding it.

Getting the apple core submerged in a few inches of dirt is a reasonably trivial task.

As he's working on it, another slime comes floating down the river from the other direction, spinning gently in the current. This one is an opaque glossy black, reminiscent of ink. It collides with the rainbow slime and the two of them start hopping aggressively at each other; their battle gradually carries them farther downstream.

That's really cool and Bruce wishes he had a camera. He makes sure he remembers this spot and how to get back to his house from here and starts exploring downstream.

Downstream, the forest remains a forest; there's another apple tree a little ways farther along, and across the river a little ways farther than that the grassland makes an extremely abrupt, grid-aligned transition to snowy ground sprinkled with spruces.

A slime hops out of the snowy area and into the river, where it struggles against the current to reach the other side; it sparkles in the sun, wreathed in glittering frost.

Oooh, that's a pretty slime. He wonders if these things can be domesticated. Also, he has to know what the temperature gradient is like over there. It might be exploitable for infinite free energy, and even it not he bets it's neat. Can he ford the river without getting soaked by putting a beam or two across it?

He can! Beams can only be attached to the sides of walls, but he can build a one-block-high wall and stick a beam to the side and bridge the river in this fashion. Two beams next to each other with floors on top, if he's feeling really fancy, although at that point the wood expenditure gets significant.

The temperature gradient between snowy and non-snowy zones is pretty sharp. There's a little bit of chill creeping across the divide, and a little bit of heat escaping in the other direction, but for the most part, the snowy zone feels like a brisk winter day and the river and grassland feel like spring.

Amazing. Between this and the torch that doesn't burn down, if his surroundings are real at all he's in a place with different laws of thermodynamics. In which case it's anyone's guess how he's managing to exist as organized matter. Maybe he's been put into some sort of fully immersive VR; that would make more sense than either "all of this is real" or "his brain is somehow generating all of it while he feels almost completely lucid". It isn't a complete explanation and raises further questions, of course, but it's a working hypothesis. He eats another apple, and this time tries picking the seeds out of the core to see if they can he planted like acorns.

In attempting this he discovers... that there aren't any seeds in the core of this apple.

Sigh. Of course not. That would be too familiar and convenient. Maybe apples here are like bananas and can only reproduce from cuttings. Whatever; at least he can eat the whole thing. He goes back across his bridge and starts exploring further downstream; the frost zone is interesting but cold and the river is too good at keeping him from getting lost to give it up.

The river curves, blockily, off to the left; as the sun sinks in the sky, the river bends toward it, until he reaches the edge of the forest facing almost due west. Ahead, there's another grassland; to his right, the river swings back northward for a short distance, broadening gradually, before pouring itself into a glittering ocean. The grass is too tall for him to see clearly past it, but on the far side of the river there's a clearly visible line where the snowy area stops and a sandy shore begins; standing on the shore between the snow and the ocean, there is a tall palm tree, with heavy bunches of dates hanging from its fronds.