A wildcard in dogs can be a pet that is:

1. Unpredictable in behavior
2. Full of energy and playful
3. Mischievous and prone to getting into trouble
4. Independent and stubborn at times
5. Loyal but also likes to test boundaries
6. Intelligent and clever, often finding creative ways to get what they want
7. Active and adventurous, loving to explore and investigate
8. Playful and fun-loving, bringing joy and excitement to their owners
9. A bit quirky and eccentric, with unique personality traits
10. Always keeping their owners on their toes!

Some breeds that might be considered wildcards include:

- Fox Terriers
- Jack Russell Terriers
- Pomeranians
- Chihuahuas
- Beagles
- Bulldogs
- Pugs
- Shih Tzus

Remember, every dog is an individual, and even breeds known for being wildcards can have calm and gentle personalities.