Zeus is far more powerful than normal homies, being made from a fragment of Big Mom’s very own soul. This gives the cloud a will strong enough to resist the soul projection of the Yomi Yomi no Mi.
As a cloud, Zeus can fly, produce both normal and “sweetened rain”, and attack with powerful bolts of lightning strong enough to defeat Vinsmoke Judge in one hit! Zeus can also carry objects and people while flying, as seen when it transported Pudding and Sanji to the wedding venue and when it carried Big Mom to chase the Straw Hats. Zeus can fly at incredible speeds, enough to catch up to the Straw Hats, who had a significant headstart, while carrying Big Mom.
Zeus is very loyal to Big Mom and will come to her when she summons it.
However, while generally loyal to Big Mom, Zeus shares her extreme gluttony and particularly enjoys eating thunderclouds. Zeus was willing to disobey direct orders from Big Mom as long as Nami kept feeding it thunderclouds. However, it is capable of reason and learning from its mistakes, as it became very angry when Nami tried feeding it again, though its anger made it open to attack.
After being sliced in half by Brook and then drained of electricity by Nami, Zeus’s size was greatly reduced, enough to be held in one hand. Nami then captured Zeus and threatened it, stating that she would kill it if it did not serve her.
Nami is already a smart woman, capable of manipulating the weather. If Zeus becomes her fighting companion, then “Cat Burglar” will finally be a truly fearsome opponent!