Nefertimon, the "Angel of Light", is the form that Gatomon takes
when she Armor Digivolves using the Digi-Egg of Light. Her name is
derived from the ancient Egyptian queen, Nefertiti.

Gatomon first became Nefertimon on the day the Digi-Egg of Light
was found. Gatomon, Kari, T.K. and Patamon had ended up in a cave
after escaping some Dark-Ringed Tyrannomon. Kari managed to obtain
the Digi-Egg and unleashed its power, allowing Gatomon to Armor
Digivolve to Nefertimon. Nefertimon became a valuable fighter during
the Digimon Emperor's reign of terror as well as during the chaos
caused by Arukenimon, Mummymon, and BlackWarGreymon.

Attacks

Rosetta Stone: A pink beam of light erupts from
Nefertimon's back, and stone slabs shoot forth from it. 
Queen's Paw (Nile Jewelry): Gems are fired from
Nefertimon's paws. 
Cat's Eye Beam (Curse of Queen): Beams of light fire from
Nefertimon's headdress. 
Golden Noose (Sanctuary Bind): Nefertimon partners with
Pegasusmon to bind enemies with a rope of golden light.
Source:http://en.wikipedia.org/wiki/Nefertimon#Nefertimon