"Wishing you happiness as big as Lord
Ganesha's appetite, life as long as his trunk, troubles small as his
mouse and moments as sweet as his laddus"
Happy Ganesh Chaturthi
As per the Mudgalapurana, there are eight incarnations of Lord Ganesha and appear in the following order:
Lord Ganesha in his first incarnation as Vakratunda (twisting trunk), used lion as his mount and made the demon Matsarasura (jealously) surrender to him.
Lord Ganesha in his second incarnation as Ekadunta (single tusk), used mouse as his mount and made the demon Madasura (arrogance) surrender to him.
Lord Ganesha in his third incarnation as Mahodara (big belly), used mouse as his mount and made the demon Mohasura (delusion) surrender to him.
Lord Ganesha in his fourth incarnation as Gajanana (elephant face), used mouse as his mount and made the demon Lobhasura (greed) surrender to him.
Lord Ganesha in his fifth incarnation as Lambodhara (pendulous belly), used mouse as his mount and made the demon Krodhasura (anger) surrender to him.
Lord Ganesha in his sixth incarnation as Vikata (unusual form), used peacock as his mount and made the demon Kamasura (lust) surrender to him.
Lord Ganesha in his seventh incarnation as Vighnaraja (king of obstacles), used serpent as his mount and made the demon Mamasura (possessiveness) surrender to him.
Lord Ganesha in his eighth incarnation as Dhoomaravarna (grey color), used mouse as his mount and made the demon Ahamkasura (pride) surrender to him.
References: Wikipedia, Lord Ganesha (Book by Manoj Publications)