theres two type of beta actually. One is the fancy type beta while the other type is the short tail beta. fancy beta are just for display and not really suitable for dueling .The short tail beta are much more for dueling. One thing about fancy type beta is that fancy beta are actually home breed type,which means it is breed for display.While the short tail beta or not much fancy are the ones mostly caught from wild.Thats why that differs abit. Wild ones tends to have stronger endurance compare to the home breed which is alway safely and happily swimming around in your fish tank.That may explains abit why nowadays betas sold in LFS are much more weaker.Because they are mostly imports from thailand and other country.They were breed to display rather than breed to duel.To those who really wanted fierce betas,go for wild ones.LFS betas mayb train to be fierce but compared to the wild ones, it is still weaker.And also one thing about those betas cant create bubble nest is also depend on what u feed it.It is best to feed betas "life food" instead of "packed or flaked food".