I recommend reading the deck list before reading the following (long) primer. After reading over the deck list, you're likely to be wondering... does it work? Really? How?
-------------------- This Deck Works: How and Why --------------------
1) This is a purely defensive deck. Your goal is to shut down and eventually deck the opponent. This is usually impossible in Standard, but not ~quite~ as hard as it sounds in Legacy.
2a) This is a prison deck. You prevent the opponent from taking a winning action. They can play cards, but you prevent them from using their cards to kill you. They can play creatures, but not attack with them. They can play their combo cards, but can't activate them. They can play damaging spells, but the damage is reduced to zero. That's the "idea" of a prison deck.
2b) A prison deck can "work" because you can guess what cards (most of) your opponents are playing (and not playing), and you can guess how they're going to try to kill you. You make intelligent educated guesses about their strategy, then lock them down.
3) This is a recursion deck, which new players find disorienting. The pilot of this deck will replay many cards from the graveyard. Almost all the cards in this deck are lands, which can be recovered from the graveyard with Life from the Loam, or artifacts, which can be recovered from the graveyard with Academy Ruins. If you draw even one Misty Rainforest, expect to re-use it.
4) This is a card advantage deck. You'll want to "dredge" Life from the Loam as often as possible. Since Life from the Loam puts three new cards in the graveyard each turn, it's almost like drawing three cards per turn. (Almost.)
5) This deck wins by decking the opponent. Once the opponent is satisfactorily "imprisoned" and unable to win, you speed up the decking process by using Jester's Cap every turn. This requires eight mana (four to play the Cap, two to activate the Cap, two to activate Academy Ruins so you re-draw the Cap).
-------------------- How to Play: Strategy --------------------
A prison deck is defense-oriented, so the play strategy depends on the opponent. It's one of the few types of decks where you'll prefer to go second, so you can witness the opponent's first turn, guess what kind of kill they're going for, and then react to imprison them.
Versus a creature deck: play multiple copies of Ensnaring Bridge as quickly as possible -- "Three on the battlefield, one in the hand." Of course, to make Bridge effective, you'll want to empty your hand each turn (use Manabond, or don't take more cards with Loam than you can play). Pithing Needle has limited use: it stops Aether Vial, as well as Seige-Gang Commander or Rishadan Port in Goblins, Qasali Pridemage or Grim Lavamancer in Zoo, and Wasteland in Merfolk (that's why we only run one Wasteland ourselves). You can also use Pithing Needle to stop fetchlands. After sideboarding, Pithing Needle should stop their "hate" cards (Tormod's Crypt, Relic of Progenitus, etc).
Versus non-Storm Combo: Play multiple copies of Pithing Needle, guessing their kill card: "Three on the battlefield, one in the hand." Pithing Needle shuts down a variety of the standard combo kills in Legacy (Grindstone, Survival of the Fittest, Sacred Mesa, Goblin Charbelcher) as well as weird combo kills (Grim Monolith + Power Artifact, for example). Since they'll have ways to destroy your Pithing Needle, play multiple Needles naming the same card. You can sideboard out Bridges/Tabernacle/Chasms for Stifles/Ports, allowing you to stop hate like Tormod's Crypt, or slow the opponent by disrupting fetchland use and stopping quick combos.
Versus a Mill deck: like Combo, but sideboard in Darksteel Colossus, whose replacement effect protects you from milling.
Versus a Storm deck: Nothing like other Combo. The play here's weird. One use of Jester's Cap will probably neuter them. Play Pithing Needle naming Chrome Mox to slow them down, and use and reuse Wasteland & Ghost Quarter (on your own turn) to wipe out their mana base. Starve them out and hunt for Cap (Gamble, Intuition, dredge Loam, whatever). Their typical protection cards (like Duress) are less effective, since they target nonland cards, but you have lots of dud cards like Tabernacle and Bridge. Just focus on starving their mana base until you can get Cap to remove their Storm-kill cards. Sideboard your duds for Jace, Crucible, Stifles, and Ports.
Versus a burn deck: find and play Exploration/Manabond ASAP, and lock the player down with Glacial Chasm and Zuran Orb. Protection versus burn is the main reason this deck plays Zuran Orb mainboard. Name Grim Lavamancer with a Pithing Needle. Sideboard for Ports, Jace, and Mindslaver.
Versus light counter-control, use the usual tricks to get them to counterspell poorly. Sideboard in Rishadan Ports and Jace.
Versus heavy counter-control, e.g. Counterbalance or Team America: play to mana-starve the opponent by re-using Ghost Quarter. Name Sensei's Divining Top with Pithing Needle ASAP.
-------------------- Weaknesses --------------------
This deck is especially weak to Extirpate and graveyard hate, and is weakened by Pithing Needle. Versus a deck that could run Extirpate, sideboard in Crucible (in case they Ex your Loam), Jace, and Mindslaver. Versus a deck that runs graveyard hate, try to neuter the hate with Pithing Needle, and sideboard in Crucible and Stifles.
The deck also dies to speed kills if it can't get its defenses up in time. Other than Mox Diamond, the deck runs no acceleration, and it's search-heavy, which means it can be slow. Careful when choosing to keep or mulligan a hand.
-------------------- Currently Testing --------------------
Is the balance of fetchlands and dual lands appropriate? Should I remove the dual lands entirely, instead running more fetch lands and basic lands? (A lot of this depends on how Wasteland-heavy the metagame is.)
Now that Survival of the Fittest is banned, should I reduce the number of Pithing Needles to 3 and include a solitary Trinisphere, Defense Grid, or other anti-control measure?
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This is an experimental Lands Prison deck, using the Bridge & Needle mechanic. Reading it over, you're probably wondering... does it work? Really? How?
1) It's a purely defensive deck. Your goal is to shut down and eventually deck the opponent. This is usually impossible in Standard, but not ~quite~ as hard as it sounds in Legacy.
2a) It's a prison deck. You prevent the opponent from taking a winning action. They can play cards, but you prevent them from using their cards to kill you. They can play creatures, but not attack with them. They can play their combo cards, but can't activate them. They can play damaging spells, but the damage is reduced to zero. That's the "idea" of a prison deck.
2b) A prison deck can "work" because you can guess what cards (most of) your opponents are playing (and not playing), and you can guess how they're going to try to kill you. You make intelligent educated guesses about their strategy, then lock them down.
3) This is a recursion deck, which new players find disorienting. The pilot of this deck will replay many cards from the graveyard. Almost all the cards in this deck are lands, which can be recovered from the graveyard with Life from the Loam, or artifacts, which can be recovered from the graveyard with Academy Ruins. If you draw even one Misty Rainforest, expect to re-use it.
4) This is a card advantage deck. You'll want to "dredge" Life from the Loam as often as possible. Since Life from the Loam puts three new cards in the graveyard each turn, it's almost like drawing three cards per turn. (Almost.)
5) This deck wins by decking the opponent. Once the opponent is locked down, you speed up the decking process by using Jester's Cap every turn. This requires eight mana (four to play the Cap, two to activate the Cap, two to activate Academy Ruins so you re-draw the Cap).
How to Play: Strategy
A prison deck is defense-oriented, so the play strategy depends on the opponent. It's one of the few types of decks where you'll prefer to go second, so you can witness the opponent's first turn, guess what kind of kill they're going for, and then react to imprison them.
Versus a creature deck: play multiple copies of Ensnaring Bridge as quickly as possible, and empty your hand each turn (use Manabond, or don't take more cards with Loam than you can play). "Three on the battlefield, one in the hand." Pithing Needle is not completely worthless: it stops Seige-Gang Commander in Goblins, and Qasali Pridemage & Grim Lavamancer in Zoo.
Versus Combo: Play multiple copies of Pithing Needle, guessing their kill card: "Three on the battlefield, one in the hand." Pithing Needle shuts down a variety of the standard combo kills in Legacy (Grindstone, Survival of the Fittest, Sacred Mesa, Goblin Charbelcher) as well as weird combo kills (Grim Monolith + Power Artifact, for example). Since they'll have ways to destroy your Pithing Needle, play multiple Needles naming the same card.
Versus a Storm deck: The play here's weird. One use of Jester's Cap will neuter them. Play Pithing Needle naming Chrome Mox to slow them down, and use and reuse Wasteland & Ghost Quarter (on your own turn) to wipe out their mana base. Starve them out and hunt for Cap. Their typical protection cards (like Duress) are less effective, since they target nonland cards, but you have lots of dud cards like Tabernacle and Bridge. Just focus on starving their mana base until you can get Cap to remove their Storm-kill cards.
Versus a burn deck: find and play Exploration/Manabond ASAP, and lock the player down with Glacial Chasm and Zuran Orb. Protection versus burn is the main reason this deck plays Zuran Orb mainboard. Name Grim Lavamancer with a Pithing Needle.
Versus light control, try to use Exploration and Manabond to draw counterspells.
Versus heavy control, e.g. Counterbalance or Team America: play to mana-starve the opponent by re-using Ghost Quarter. Name Sensei's Divining Top with Pithing Needle.