Talk:Dragon of the Sun, Bal Dragon/@comment-24971427-20160303090700/@comment-26392338-20160307220959

tl;dr - Not per battle, just per ability chain.

Lets say a vanilla monster makes an attack; the non-turn player has the timing to cast a spell, which can be countered by the turn player. Since two cards effects have been chained together, that's the end of that ability chain.

In the case of Bal Dragon, its ability goes off when it attacks, so when the non-turn player casts a spell in response to it, that also counts as two card effects having been chained together, ending the ability chain.

Two monster abilities chaining together also counts as a chain; for instance, if you used meteor rain's effect in response to asmodai's on-drop effect.