You have some great answers here already but there are a few more Pokemon available for you to use. Most of them are Ground types but there a couple non-grounds in here.
Mamoswine @ Leftovers
Ability: Thick Fat
EVs: 252 Atk / 252 HP / 4 SDef
Adamant Nature
- Stealth Rock
- Earthquake
- Icicle Crash
- Stone Edge
First off is an offensive Rock setter. Mamoswine doesn't have "Good defense" but what he does have is good bulk. With a base stat of 110 HP he can tank a lot of hits. Coupled with his Thick Fat ability he can tank several attacks being thrown at him. He also has a godly attack stat allowing him to punch holes in teams that don't have a reliable counter.
Donphan @ Leftovers
Ability: Sturdy
EVs: 252 HP / 178 Atk / 80 Def
Adamant Nature
- Earthquake
- Stealth Rock
- Head Smash
- Rapid Spin
Donphan has a base 120 Defense giving him so great tanking capabilities. He also has the ability to set up Rocks and Spin for your team. With coverage moves like STAB Earthquake, Head Smash, Seed Bomb, and Ice Shard at his disposal and a base 120 Attack stat he, like Mamoswine, can punch holes in non-defensive Pokemon who aren't prepared to deal with him. He also has tusks, who doesn't want a Pokemon with tusks?
Heatran @ Leftovers
Ability: Flash Fire
EVs: 252 SDef / 252 HP / 4 SAtk
Calm Nature
- Lava Plume
- Substitute
- Toxic
- Stealth Rock
While what I have here is Heatran's Specially Defensive spread you can also run it as a Defensive spread. Lava Plume also provides a good chance to burn your foe allowing Heatran to tank some physical attacks. Substitute and Toxic provide some good stall, while Rocks can be set up with ease a lot.
Metagross @ Life Orb
Ability: Clear Body
EVs: 252 Atk / 252 HP / 4 SDef
Adamant Nature
- Stealth Rock
- Earthquake
- Meteor Mash
- Ice Punch
Another offensive setter Metagross has a great Defense stat and a good typing. As with Mamoswine and Donphan he also has a great attack stat allowing him to punch holes in a lot of teams. Earthquake and ice Punch are coverage while Meteor Mash is main STAB with a good chance to raise attack.
Gliscor @ Toxic Orb
Ability: Poison Heal
EVs: 184 Def / 252 HP / 72 Spd
Impish Nature
- Stealth Rock
- Protect
- Earthquake
- Taunt
Reading the answers I can't believe none of you mentioned Gliscor. He has great speed allowing him to taunt walls like Jellicent, while also getting the drop on some of the slower set-up physical attackers. Protect gets him some healing, Earthquake is STAB and for killing off low hp Pokemon.
Landorus-Therian (M) @ Leftovers
Ability: Intimidate
EVs: 248 HP / 148 Def / 112 Spd
Naive Nature
- Earthquake
- Stealth Rock
- Hidden Power [Ice]
- U-turn
Landorus coupled with Intimidate and the right EVs can easily tank physical attacks. He also makes a great addition to VoltTurn teams with U-Turn. HP Ice is coverage against Gliscor and Dragon/Ground types, while Earthquake is Main STAB and packs a heck of a punch.
Hope this answer helps you see how many options there are out there. Have fun building and battling!
