Spider Mines Q: The name is self-explanatory. Use these as wards or ambushes. They last 35 seconds once armed and arm in approximately 1.5 seconds. To compare, Abathur's mines last 90 seconds. However, despite their small duration, don't be afraid to spam them: Hammer has no mana problems at any stage in the game.

Concussive Blast W: Use this to get Sonya off your face. Can also be used to knock someone into your team if you flank them in a gank. Recommended to use it only defensively in teamfights.

Siege Mode E: DO NOT USE THIS. I'm joking of course, but the easiest way to mess up as Hammer is to siege at the wrong time. It has a cast time and it adds ZERO direct damage vs heroes. The splash is extremely small and low damage, the main benefit is bonus damage vs structures and increased range. In teamfights, if you aren't moving, that range isn't going to do much for long. If you can set up and get a few max range shots before they engage, go for it, but NEVER siege during a teamfight. Main use is when you're in a safe position to burn a keep or fort.

Napalm Strike R: Minion clear, zoning, burst. This ult has it all on a 6 second cooldown. Spam it.

Blunt Force Gun R: Hit level 20 and aim this at one of their keeps. Seriously though, don't pick this ultimate. Naphalm Strike does everything this does but at a twelfth of the cooldown.

Thrusters Z: Escape as well as kill secure. IMPORTANT: If you use this while in Siege Mode, you will instantly desiege.

If a talent is not mentioned, I do not recommend it in any situation.

Level 1:
Ambush
Makes your first attack hit for half of a squishes health. Unfortunately, its tied to sieging. I don't like sieging. Ten attacks using Advanced Artillery gives the same benefit and none of the downsides.

Level 4:
Vigorous Assault
Take this for more sustain but less burst. I like effortless burst.

Level 13:
First Strike
Slightly better Giant Killer vs squishes as well much more building damage. The drawback is too much for me to recommend it normally, however. Take it if you're confident in your positioning and the enemy team lacks all dive and poke. So basically, a standard QM.

Level 16:
Hover Siege Mode
Graduating Range
Both significantly increase the usability of Siege Mode. Take Hover if you don't have a lot of time to set up, take Graduating if you do. The reason I recommend Executioner is that it doesn't matter how safe your siege is if the enemy is dead.

Level 1:
Resistant
You can root yourself to reduce the duration of roots. Wow.
Regeneration Master
You're a literal tank, not a figurative one. Build damage.

Level 4:
Excessive Force
Upgrade your autos instead.

Level 7:
Slowing Mines
Too little effect.
Hyper-Cooling Engines
Like Slowing Mines, just can't compete with First Aid.

Level 10:
Blunt Force Gun
See Abilities above.

Level 13:
Bullhead Mines
Once upon a time, this made every mine knockback and you could stunlock anyone with them.
It doesn't do that anymore.
Barricade
Good for Trump, not for you.

Level 16:
Mine Field
I hope you've gotten it by now. Mine talents = bad.
Stoneskin
Still not a tank. Nope.

Level 20:
Orbital BFG
Requires taking BFG.
Advanced Lava Strike
Base range is plenty big enough.
Fury of the Storm
Hammer never has any problems killing minions and this provides far less sustained damage than Nexus Frenzy.

Not all of these are bad talents, but they are all outclassed by other talents in their tier.