It's interesting to see that the males of all the savage Betta races have one common trait: They are very gentle in looking after their breed.
All alone they build a confortable nest out of bubbles, where they put the eggs the females abandoned to their fate. Then they ensure the security of their offspring until these are old enough to swim on their own.
Even the most ferocious warriors can be the most tender parents!
To this occasion, the "Betta" set was renamed "Red Betta".