Well they're nothing set in stone, just what I feel like that day.
For BW days I'll just use BW exercises such as Lying Hip Swings, GHS, Back Ext, V-ups, ...
For Explosive core days, I'll often do GHS, back ext, GHR...but done explosively.
Heavy days are usually Overhead Sit-ups with Dumbbells, GHS weighted, windmills, TGU...One of my current favorites is a little diddy like so:
3-4 rounds of:
3 Turkish Sit-ups
1 Turkish Get-up
I'll take a rest between sets/rounds. I like using a Oly bar with weights for that one...
For sets and reps I use what my level and strength can handle. There's no magic bullet.
Healthy body sick mind...