I need something broken

[Eldariel]

You don't want something broken. That'd just disjoin the game. You want something extremely powerful, that you can scale down as desired. Core Druid played by a true master is probably the strongest thing this side of blatant gamebreaking (permanent Polymorph Any Object on low level; purchase casting - Candle of Invocation; bind Efreet, wish for anything, for example more Candles for more Wishes - Dust of Sneezing and Choking; no-save basically anything is disabled for long enough). Wizards and Clerics are also amazing, but Druids have more to play with early on (and on level 17, they still keep up thanks to Shapechange).

Basically:
Feats:

• Natural Spell: Take on 6, you're on your way to godhood.
• Leadership: If allowed, take on 9, pick e.g. Druid or Wizard Cohort, win everything forever.
• Augment Summoning: Druid has the best summons in the Core and can use them spontaneously, it's rarely wasted.
• Multiattack: Good for fighting in Wildshape.
• Improved Trip: Good for fighting in Wildshape.
• Quicken Spell/Extend Spell/Spell Penetration/Greater Spell Penetration: Good for spellcasting.
• Craft Wondrous Items/Craft Magic Arms and Armor: Good for getting tons of valuable equipment.

Skills:

• Concentration, Knowledge: Nature are must maxes. Concentration for a melee caster and Knowledge: Nature so you know what you're summoning and what-not. If your DM side-steps that, feel free to skimp on K: Nature tho.
• Spellcraft is a must max if you're the only spellcaster or if you want more soloability. Not that important with other party casters.
• Spot and Listen are superb and ones I'd always strive to max out as a Druid as observational talents are awesome.
• Handle Animal should take enough ranks that you can reach +10 with your Animal Companion (counting the +4). This allows you to take 10 to teach it tricks, which means you can teach all the tricks you need. Teach it combat tricks and if you need to Push it, just take 20. If you're gonna form a Druidic herd of animal helpers though or take more combat helpers á la Handle Animal Guide, you'll want to max it especially if Charisma isn't your strong suite.
• Survival is a fine skill but you get most of the uses you want out of it without a single rank thanks to your immense Wisdom. I'd save points there.
• If going for a combatant, you'd want to consider a few cross-class skills. First, Balance is very useful to have 5 ranks in simply to not be flat-footed when Balancing (e.g. on Grease, Marbles or such). Then, Tumble is obviously superb for a non-armored character; just max it if you can afford it. Then, many forms come with bonuses to Hide and Move Silently so putting cross-class ranks in those could be helpful.

Animal Companion:
Stick to canine, feline & ursine creatures, mostly. Crocodiles, dinosaurs and big creatures also tend to make reasonable options. A good line of development would be something like:
- War-Trained Riding Dog (see Riding Dog entry in Monster Manual)
- Dire Bat
- Brown Bear
- Dire Lion
- Dire Bear
- Dire Tiger

With tons of obviously solid alternatives. Of note is that riding on a Dire Bat mount on level 4 is very, very effective, and War-Trained Riding Dog with Bardings (War-Trained creatures have armor proficiencies) is better than most low-level warriors. And Dire-creatures have good Will-saves which is very welcome.

Spells:
Use most of your spellslots for battlefield control. Basically Entangle, Soften Earth and Stone, Sleet Storm, Ice Storm, Antilife Shell, etc. allow controlling enemies very well. Then you have Barkskin, Freedom of Movement, Animal Growth, Air Walk and such as very, very solid ally/animal buffs (note, you can buff your summons too; Animal Growthing a bunch of Dire Wolves is filthy). And your spontaneous summons, which also replicate spells from other lists (and Unicorns are superb healbots, Pixies are wonderful assistant casters and such, Thoqquas get you to places, etc.). And then you have a bunch of utility like Transport Via Plants, Scrying and such, and good ol' Control Winds & Giant Vermin once you get high caster level (e.g. Beads of Karma from Strand of Prayer Beads, and Orange Prism Ioun Stone, get you there fast).

Wildshape:
You can spend 24/7 in Wildshape at level 8. Almost all adventuring day on level 6. Make use of this. Take high mental stats & Con, stay in Wildshape to use animals' physicals, get Wild (enhanced) Armor & Shield, use Ioun Stones & buffs, etc. Stuff like Bears, Tigers, Deinonychus, etc. make for solid Wildshape forms. Elementals have obvious utility but aren't too good in combat.


For more details, perview the handbook. Basically tho, yeah, play a Druid and play one well and you can be however strong you want to be.