Now, this doesn't activate till level 12, but it is pretty cool when it does.
Step 1 is to be an Orc/Half-Orc hunter multiclassed as a Barbarian. This is already a pretty sweet combination since you get Rage for free at level 3, which is a nice boost of damage. However, the real gem is when you hit level 11 and gain access to a rage power. Namely, Ferocious Mount.
Once that happens, at level 12 you gain another teamwork feat, in which case you would take Amplified Rage. Now instead of simply giving your animal companion +4 Strength and +4 Con, now the two of you have +8 Strength and Con.
The beauty of doing this is that, as a Hunter, you gain free teamwork feats and thus can afford to lose some regular feats. (All you really need is Combat Expertise anyway for Pack Flanking). Those lost feats give you some powerful ooph, which stacks with your Hunter's Focus or Evolved Companion abilities. Once your animal companion gains the ability to rage, and you can make use of the Amplified Rage feat these bonuses only get bigger and as long as you are mounted you might as well be a full scaling Barbarian.
At this point, while raging and riding your animal companion you have a minimum to hit of +17/12 without even considering your base Strength score, spells, being mounted and thus taller than your opponent, your other two normal feats, or your other two teamwork feats.
All in all, if you are going into a higher level campaign or expect it to make it past level 12: Consider the Raging Hunter!