[S23B] Chaos Emperor's first phase can be killed by non-union attacks on retaliation

[mariologie]

Wesnoth 1.15.14 on Arch Linux, correct repository this time

If you reduce Argan's HP to a low amount via Elynia's union attack and successfully kill him on retaliation with any unit (here this happened with a Wraith), it successfully triggers the second phase of the fight. However, this immediately activates the second phase's events for killing Argan without the union, which halves his HP, making the fight so much easier.
IftU-Until Death replay 20210711-174056.gz