Chaos Wins!

I have a particular affinity for the rats tribe. It's a tribe with a ton of fluff and flavor. There are a large number of legends to choose from, and the discard sub-theme is a potent way of maintaining board control with otherwise sub-optimal and tiny creatures.

Some of these cards are powerful in any deck. Ravenous rats has been a tournament staple for years: Elegant card advantage attached to a 1/1 body. The legends have also seen some play, Ink-Eyes is a bomb and in this format is almost always going to have something good to grab out of a graveyard, especially if you just forced your opponent to dump a pricey creature with Hymn to Tourach. The Nezumi's are both quality cards that leverage board strength while generating card advantage as well. The Cuthroat can finish an opponent all by himself without even attacking while flipped to legendary form.

For removal options black has plenty to choose from. Nameless inversion is a good choice for this format as it can kill mid size creatures and then wipe any buff effects generated by tribe bonuses as well. The Disk is pretty much required in any mono-black deck as we have otherwise no other options for dealing with nasty show stoppers like Story Circle or problematic artifacts. Crypt rats are an earthquake/hurricane on a stick. I'm a big fan of creatures that double as removal in this format. It keeps those precious removal slots in play for either more removal or toys to help the cause.

I crammed Sword of Fire and Ice into this deck. I think the buff effect is necessary with so many small bodies. The +2/+2 is nice of course, but the card draw and removal aspect makes it one of the best equipments legal in this format.

Classic Tribal Wars - Rats

Creatures

3 Sewer Rat
3 Nezumi Graverobber
3 Nezumi Shortfang
4 Ravenous Rats
3 Crypt Rats
3 Marrow-Gnawer
2 Ink-Eyes, Servant of Oni

Spells

4 Nameless Inversion
4 Hymn to Tourach
3 Sword of Fire and Ice
3 Nevinyrall's Disk

Land

1 Pendelhaven
1 Shizo, Death's Storehouse
2 Swarmyard
2 Mutavault
2 Wasteland
4 Verdant Catacombs
2 Bloodstained Mire
1 Urborg, Tomb of Yawgmoth
10 Swamp

Rounding out the land we see staples like Wasteland and Mutavault (with fear!). I like Swarmyard and will always use this land when applicable in tribal wars. Pendelhaven is a nice touch here with so many 1/1 creatures available.

Rats are small but the disruption results of discard spells can be brutal to an opponent. If you can wipe their hand early they will have no answers to your endless horde of rodents.