These are the Digimon Isabella owns in Phineas and Ferb A-Xros The Digital World and Phineas and Ferb Xros Heart Leaps through Time.
Digimon[]
Lekismon[]
Lekismon was captured while Xros Heart was on the DigiQuartz version of the moon.
Attacks
- Moon Night Bomb: Throws against the enemy with a water bubble created by her Moon Gloves. It can cause the enemy to fall asleep.
- Tear Arrow: Shoots the enemy with a pretty ice arrow from the stickup on her back.
- Moon Night Kick: Jumps up high and comes down quickly to give a strong kick.
Mervamon[]
Mervamon was originally a freedom fighter against Zamielmon in Honey Land, forced to fight her younger cousin Ignitemon. When Xros Heart arrives to Honey Land, Mervamon saves them, and unknowingly drags them into her battle against Zamielmon. Mervamon is aided by Isabella in making Ignitemon open his eyes and stop helping Zamielmon in his evil deeds. After Zamielmon is defeated, Mervamon decides to become Isabella's partner and join Xros Heart.
From that moment on, Mervamon becomes one of Isabella's more frequently used Digimon, being more used than any other. Even after Xros Heart splits and goes their seperate ways, Mervamon stays with Isabella and protects her from harm.
After Sparrowmon gains the power to Golden Digivolve, Mervamon was pushed to the side.
Attacks
- Love Poison: Uses its glamor to exploit the vitality of the opponents that inhale the toxic mist sprayed from the Medullia's mouth.
- Madness Merry-go-round DX: Performs a spinning slash, too quick to catch with the eyes, with the Olympia Kai and Medullia, creating a tornado that instantly tears the opponents it touches limb from limb.
Monimon[]
Monimon is a young version of Monitamon, learning to be a ninja.
Attacks
Monitamons[]
When Isabella first appeared, she was shown to have three green Monitamon (later revealed to be elites) and a Monimon. Not long after she and most of Twilight joined Xros Heart, the team went to the Shinobi Zone where the three red "dropout" Monitamon joined Phineas. Monitamon are constantly used throughout the series to deliver messages to other members of Xros Heart.
Attacks
- Kadan (火弾? lit. "Fire Shot"): Creates a fireball.
- Suiryū (水竜? lit. "Water Dragon"): Attacks with a water pistol.
- Kazaguruma (風車? lit. "Wind Wheel"): Raises a wind.
- Densen (電閃? lit. "Lightning Flash"): Discharges lightning.
QueenChessmon[]
QueenChessmon, was captured by Isabella to keep her safe from Ren.
Attacks
- Heart Breaker: Impales the opponent's vitals with the swords stocked on its armor.
- Queen Stamp: Cheers up Digimon who have lost their fighting spirit.
Sparrowmon[]
Sparrowmon specializes in aerial battles and soars soundlessly at Mach speed. Because she is a person that easily gets carried away due to her moodiness, you can immediately tell whether her mood is good or bad, from whether it looks like she is flying well or badly. If she is performing highly difficult aerial acrobatics without even being asked, you can take it as unmistakable proof that she is in high spirits.
Sometime before Phineas and Xros Heart; Isabella wound up in the Bird Zone, and finds Sparrowmon's Digi-Egg, her touch hatches the Digi-Egg, and Sparrowmon becomes her faithful partner.
In Sand Zone, she attacks a group of SkullScorpiomon, and Diamondmon. However, she is held off by Diamondmon's attacks, and eventually retreat after Isabella reveals that Phineas and Ferb have the Sand Zone's Code Crown.
In the Heaven Zone, forced to watch her friend as she is engulfed in the darkness she was gathering for DarkKnightmon, Sparrowmon attempts to save Isabella when she trapped into Lucemon Shadowlord Mode's Gehanna. Before saving Isabella, Sparrowmon gains a Wrister from Phineas as a sign of friendship when he and Shoutmon support her in rescuing Isabella. This results in Phineas and Isabella Dual-Xrosing Shoutmon x4 and Sparrowmon to Shoutmon x5 who destroys Lucemon.
When Twilight is in the Forest Zone, Phineas and Shoutmon become separated from the rest of Xros Heart, and they meet up with Isabella and Sparrowmon.
After DarkKnightmon obtains the power to Digi-Xros on his own, he abandons the rest of the team. Sparrowmon then joins Xros Heart.
Sparrowmon later gains the power to Golden Digivolve to JetSparrowmon.
Attacks
- Crash Boom: Slams into foe with such speed that it appears to split into four.
- Wing Edge: Slices the opponent with its wings as it passes through them, while continuously altering its trajectory at high speeds. This technique owes everything to high-altitude technical flying.
- Random Laser: Fires the Zanahoria while flailing its arms wildly.