Size differences and occupying squares

[Keeva Marith]

I imagine that since Tiny creatures need to be in another creature's square in order to attack, that they are allowed to end their movement in another creature's square. That makes me wonder; can a Small creature end its movement in the square of a Large creature? What does the size difference need to be in order to end your movement in a larger creature's square?

[BartS]

I am not sure about that. I made a tiny robot character a self made class I guess. It's not an android like the paizo class and was looking it up. In pathfinder I could be wrong it would provoke an attack of opportunity. In starfinder the rules have very few things that provoke an attack of opportunity. That isn't one of them. Personally I would look at it as situational. I mostly house rule most of the combat rules from pathfinder. I tend to look at things as how they actually would really go. I would play it by ear.

[Fuzzy-Wuzzy]

Keeva Marith wrote:

I imagine that since Tiny creatures need to be in another creature's square in order to attack, that they are allowed to end their movement in another creature's square. That makes me wonder; can a Small creature end its movement in the square of a Large creature? What does the size difference need to be in order to end your movement in a larger creature's square?

It's absolute size that matters for sharing squares, not relative. From the CRB:

Combat wrote:

Very Small Creature: A Fine, Diminutive, or Tiny creature can move into or through an occupied square. The creature provokes attacks of opportunity when doing so.

Relative size does matter for moving through other creatures' squares w/o stopping:

Combat right after that wrote:

Square Occupied by Creature Three Sizes Larger or Smaller: Any creature can move through a square occupied by a creature three size categories larger than itself.

A big creature can move through a square occupied by a creature three size categories smaller than it is. Creatures moving through squares occupied by other creatures provoke attacks of opportunity from those creatures.

[Fuzzy-Wuzzy]

Dammit! Just noticed this is in Starfinder rules not Pathfinder rules. Allow me to change my answer to "I have no idea." Sorry!