Evolutionary pathway of cold giant planet formation. Top: evolution of the planetary mass (black line) across different growth regimes: the pebble-accretion–dominated phase (orange area), limited by the isolation mass (dotted orange line); the phase dominated by planet–planet collisions (pink area), with the critical mass required to trigger runaway gas accretion indicated (dotted pink line); and the gas-accretion–dominated phase (green area), during which the planet grows until it reaches its final mass (dotted green line) before disk dispersal (dash-dotted black line). Bottom: evolution of the semi-major axis (black line) across the different migration regimes: type I migration (light purple area), transition regime where migration slows (light blue area), and outward migration (orange area).