Roboteer

This is part of the Family Familiar achievement.

I'm creating guides for all trainers for you to follow easily. Displaying 15 different strategies here would be rather confusing, so here you go:
http://www.wow-petguide.com/index.php?m=LMechanical

Enjoy and good luck with the fights!

Master tamer Flummox:

This is a difficult battle as he has a combo of strong vs mechanical and a reduction to speed and attack.

Here is how I managed:

Sunreaver Micro-Sentry (2,1,1)
Lil' Bling (2,1,1)
Cogblade Raptor (2,2,1)

Start with Sunreaver: Extra plating, Fel immolate, Call lightning (may possibly skip extra plating but not tested)
Switch to Cogblade Raptor: Exposed wounds
Switch to Lil' Bling: Inflation
Switch to Cogblade Raptor when Lil' Bling dies and finish him off with Batter.

You could possibly switch to Lil' Bling after Sunreaver and then to Cogblade - but this deviation hasn't been tested yet.

Hope this is a help :-)

For Durian Strongfruit

1. Sunreaver Micro-Sentry - Extra plating, Call Lightning, Fel Immolate until Sunny is dead, apply Lightning on cd
2. Mechanical Pandaren Dragonling - Flyby, Thunderbolt, finish Roots with Explode, you could even reach pet 3
3. Darkmoon Tonk - easy win against Beaky

Just start in that order and don't swap until your pet dies.