Petit Dragon + Ghoul with an Appetite → Skelgon

Petit Dragon + Violent Rain → Spike Seadra

Petit Dragon + Key Mace #2 → Blackland Fire Dragon

Petit Dragon + Penguin Soldier → Spike Seadra

Petit Dragon + Obese Marmot of Nefariousness → Koumori Dragon

Petit Dragon + Liquid Beast → Spike Seadra

Petit Dragon + Twin Long Rods #2 → Spike Seadra

Petit Dragon + Electric Lizard → Thunder Dragon

Petit Dragon + Hiro's Shadow Scout → Koumori Dragon

Petit Dragon + Armored Starfish → Spike Seadra

Petit Dragon + Snakeyashi → B. Dragon Jungle King

Petit Dragon + Succubus Knight → Sword Arm of Dragon