Passive leveling

Hello
Are there any tricks to level up the passive level?
I have Cover passive level 7, i want to get it to level 8 before fusing but i been farming with the pet since yesterday and the progress didn't go above 37% didn't increase a single percentage.
and uhhh Does it level faster if i kill more mobs instead of bosses?

 

There are factors about pet skills. There are passive and active skills and your pet's starting skill level. As i said before, pet skill only on kill count and not exp. So kill more and faster is the trick.

 

Thank you so much. I understand this now but I have one more question lol
"kill more is the trick"
Does the pet has to hit all the mobs i kill? Or can I just use storm and it stills counts?

 

Dumping a lot of storm just count (just 1 coz only 1 is targeted BY THE PET) lemme categorize an example of grind action.
You kill a target with pet doing nothing- 1 pt
Your pet hit the target- 1 pt
Pet use skill- 1 pt from all target hit.
NOTE: all example above are not flat numbers since i don't know the correct value.

 

if your pet has the 'skill boost' type, passive skills gain bonus exp from using active skills.
for every other type, passive skills level with kill count only.

 

Lmao i see... I thought the passive level with usage. Like the passive "Cover" i thought it'd level the more damage i take, so if stand and take damage but see no progress lmao.

Thanks guys!