Honestly, I'm not really sure on this one. There are many choices to be had, but if I had to pick one...
Swampert. Yeah, Pokemon can't speak human languages (Unless we look at some of the anime's less memorable episodes, as one reveals that Team Rocket's Meowth literally learned English by listening in on language classes), but Swampert is a dependable Pokemon. They stand about as tall as an average human, and have immense strength, up to the point of being able to easily pull off what it took a whole Jeager to do in Pacific Rim (For those who haven't seen it, a Jeager drags a boat and swings it at a Kaiju). They can act as a flood early warning system, as it can detect even minute changes in the sounds of waves using its fins. Not to mention that Swampert really only has one weakness, that being any Pokemon that can manage to get off a Grass-type move that not only gets past Swampert's naturally tough defenses, but also manages to knock it down.