Magmamon appears in Digimon X and Y. It's most well known appearance would be his partnership with Takeru Akashi.
Magmamon is a Lizard type Digimon that appears in Digimon X and Y. It's appearance is extremely similar to Veemon, except it is red and has a flame in the V.
These are his digivolutions:
In-Training: Embermon Champions: Flamarimon, GoldFlamarimon Ultimate: Infurimon Megas: GigaFlamarimon, SparkGreymon Y Evolution: Kiyomon