Conditional card for low level batteries

i have a custom:battery-state-card that i downloaded form hacs. check it out if you are not familiar with it, as it is a great monitor tool for devices with batteries.
now i want to add a conditional card to display on my main dashboard just the entities with a battery level that is under 20%.
what would be the best way to do that?
do i need to manually add the condition per entity for each device i would like to display?
cheers

Hi, have a look at the Entity Filter Card

thanks, this just might be what i was looking 4.