

Lucian and Nami must establish lane dominance through trades before Nautilus finds a high-impact hook.
Abuse Nami's E (Tidecaller's Blessing) to proc Lucian's passive and Electrocute, forcing Kai'Sa out of lane or into kill range.
Getting caught by Nautilus Q without minions, leading to an isolated Kai'Sa Q and passive proc.
Nami standing too far back, leaving Lucian to 1v2 the lane pressure.
Wasting Nami's Bubble (Q) on a moving Kai'Sa; save it for when she is CC'd or channeled.
Lucian dashing forward when Nautilus has all cooldowns available.
Nautilus wants to find a hook on the squishy Nami or Lucian to let Kai'Sa stack her passive.
Post-level 6 when Nautilus has point-and-click CC and Kai'Sa has an execute/gap close.
Position aggressively but vertically behind minions. Punish Nautilus with autos every time he misses a Q.
Electrocute or Aery on Nami to maximize trade damage; Manaflow Band is mandatory for sustain.
Max W (Ebb and Flow) first for trading power, followed by E (Tidecaller's Blessing) for Lucian's scaling.
Rush Imperial Mandate; the mark is easily popped by Lucian's passive for massive burst damage.