The Cloud Tops are a new area in Pokemon Genesis that is navigated with HM02 (Fly). However, instead of flying to different cities using Fly, the Cloud Tops can be accessed. Depending on where you are ion the ground and what time it is the color and weather conditions of the Cloud Tops will change. Different Legendary Pokémon can be accessed at different times. Also, Sunrise Spire can only be accessed during the morning; the same is with Sunset Spire during the night.
A massive anvil cloud situated high in the Cloud Tops. Like other parts of the Cloud Tops, its weather and shape changes drastically in different weather conditions. By exploring different parts of the Main spire you can find different Pokémon, items, and Legendaries. Legendaries: Articuno (Snowing), Cresselia (Morning), Moltres (Bright Sunlight), and Zapdos (Raining)
This spire in the northeast part of the Cloud Tops has a pinkish tint. Legend has it that roars of thunder come from this spire Legendary: Palkia
Spire Of Old Legend
Upon catching, seeing, or defeating all Legendary Pokémon, you will receive the Sacred Key, an object that allows you to enter the Spire Of old Legend. The only real thing of interest is the final Legendary, Arceus. Legendary: Arceus
This spire in the northwest of the Cloud Tops is inaccessible at any time other than the morning. It glows blue. Legendary: Latios
This spire in the southwest of the Cloud Tops is inaccessible at any time other than night. It glows a blood red. Legendary: Latias
A spire said to have a connection with the rotation of Earth. It has a sickly green color. Legendary: Dialga