Wouldn't it be cool if giant monsters were on giant planets? Of course it would be, but unfortunately physics doesn't really like that idea. Big planets make things on them need more support, so being big sucks on big planets. It's alright on teeny ones, but bad on big ones. You'd also probably want high pressure on the planet, and low temperatures, but let's forget about that.
So how could one make it not suck to be big on such a planet.
Well....we could make the planet spin faster. Now, these big monsters, effectively, weigh a bit less. They would have to be slow, because the energy to move them (due to inertia) would be the same, so you'd probably looking at creatures with big support structures and less muscle adjacent structures?
Problem, of course, people have asked about how fast the earth would need to spin to make things weightless, of course that would destroy a planet...but what if the question was, instead,
Edit: To keep it simple, I'd like to know if a planet could (effectively) offset 10% of its gravity through rotating fast, without flinging itself into a cloud of space dust.