Find the hidden black cats of Chronopolis. Their primary tell is their meowing.
Find one on the brick bridge over the main road in Medieval England.
One just in front of the Sakaarward side of the Asgard palace.
Atop the roof of the Dragon Cave temple in K'un Lun
In a dark corner of a dark building in Dark Manhattan.
Inside the bin-like building at the Sakaar edge of Nueva York, under the T-junction.
Atop the corewardmost pyramid (the one that doesn't have Stan Lee being abducted by aliens).
At the lower level of Kang Spire, near the road from Hala
On a building toward the Egypt side of Hala.
Mid-level of a Hydra hi-rise
In a narrow gap between buildings in Attilan
Your reward for finding tenfold Tiddles is the the Black Panther Jet. Logical.