Since there is apparently NOTHING ♥♥♥♥ ELSE in the place we are, where else can we go (this means learn to be more descriptive/have more diverse environments.)

You divide until you are 17 in number.
There appear to be multiple vessels, some larger, some smaller than the one you rode to this area.
There's also an opening at the top of this area.
You have 100 energy remaining.
There are multiple benign and independent cells in this area.
There is a constant, regular movement.

Anything that looks particularly dangerous? If not, consume ♥♥♥♥ until something happens/you're full. Also send one cell to inspect railroad tracks opening up top.

You consume until you reach maximum energy, 3400.
It appears that a gas is brought in through the opening up top.
you have 3400 energy remaining.
You come across a cell which seemingly has attained conscious thought and consume it.
2000 energy for a very rudimentary brain upgrade without cell requirement, 4000 for a more advanced mind, 10000 for a sentient mind.

2000 on the brain thingo, 1000 on new cells, and further inspect gas thingy. This means we are in the lungs. I HAVE A PLAN.

You multiply until you are 37 in number.
You gain a simple brain, not much more than cause and effect.
you have 400 energy remaining, out of a possible 7400.
10 cells are used as brain cells and cannot be used as energy storage or absorbtion of other cells.
Possible energy reduced to 5400.

What does new brain allow us to do, exactly?

Perform cause and effect recognition as well as minor reasoning skills.

I mean in game terms. Considering all decision making is done by us, those are both ♥♥♥♥ USELESS.

It allows advanced communications, allowing cells to be many areas farther away than usual, as well as the ability to develop new traits without absorbing the cells with those traits first.
You currently have advanced communication, and a second upgrade will unlock traits without absorbtion.
The third upgrade will allow you to become a sentient being.

Make something interesting happen or I'm going to keep dividing and refilling. In other news, consume non-muscle cells until full on energy.

You now have 5400 energy remaining.
There seem to be new cells emerging from the blood vessels in this area.
They appear to very rapidly absorb your cells.
2 brain cells and 7 normal cells are lost.
you now have 4000 energy remaining.

Bail out bail out bail out. Wait, that poison jet trait. Move down a blood vessel as far away from the whiteys as you can and evolve that trait. It may be enough to throw them off our trail.

You upgrade your poison trait to the final level, giving you a jet of sorts.
3200 energy remaining.
Your cells retreat down a blood vessel, venting poison as they go.
2 more cells are lost during the retreat.
2800 energy remaining.
This area is new, the constant movements are gone, and there seem to be more benign cells, it will take some time to ascertain their use or any traits they may have.

Should take less time considering recent brain upgrade. I propose we say ♥♥♥♥ it and burrow into the side of the wall, replacing benign cells with our own cells, establishing a home base of sorts. We can store brain cells in here, giving us a bit of range of how far the cells can go, and if they need to go farther, send out additional brain cells with the packs. Give me some energy requirements, son. Also possible ability to make tougher cells for more energy (outer walls of home base?)