Annoyingly, it doesn't have an equivalent of Draco Meteor like Kingdra. But its special attack might be sufficiently higher that it hits just as hard regardless.Inteleon can learn Focus Energy via TR. Use a Scope Lens on it and it could have a niche Sniper Critical Hit set that can be used outside of Rain teams due to its already high speed.
(Also Critdra can't get a speed boost from the rain because it has to run Sniper)