IW-EX-8: Field of Forgotten Water
In general, I aim to defeat Sui-Xiang as quickly as I can with my best team, especially in the last phase. The boss becomes more dangerous the longer the battle lasts.
If Sui is not defeated in 9 minutes after the operation starts (which will be extended by an additional minute when He enters His third phase), He will go invulnerable and unleash a golden shockwave that causes the player to lose 999(!) Life Points, effectively resulting in an instant mission failure.