diff --git a/catanatron_core/catanatron/models/actions.py b/catanatron_core/catanatron/models/actions.py
index 9bb414dc..553cbcf2 100644
--- a/catanatron_core/catanatron/models/actions.py
+++ b/catanatron_core/catanatron/models/actions.py
@@ -298,25 +298,24 @@ def inner_maritime_trade_possibilities(hand_freqdeck, bank_freqdeck, port_resour
     trade_offers = set()
 
     # Get lowest rate per resource
-    rates: Dict[FastResource, int] = {WOOD: 4, BRICK: 4, SHEEP: 4, WHEAT: 4, ORE: 4}
+    rates = {res: 4 for res in RESOURCES}
     if None in port_resources:
-        rates = {WOOD: 3, BRICK: 3, SHEEP: 3, WHEAT: 3, ORE: 3}
+        rates = {res: 3 for res in RESOURCES}
     for resource in port_resources:
-        if resource != None:
+        if resource is not None:
             rates[resource] = 2
 
-    # For resource in hand
-    for index, resource in enumerate(RESOURCES):
-        amount = hand_freqdeck[index]
-        if amount >= rates[resource]:
-            resource_out: List[Any] = [resource] * rates[resource]
-            resource_out += [None] * (4 - rates[resource])
-            for j_resource in RESOURCES:
-                if (
-                    resource != j_resource
-                    and freqdeck_count(bank_freqdeck, j_resource) > 0
-                ):
-                    trade_offer = tuple(resource_out + [j_resource])
-                    trade_offers.add(trade_offer)
+    # For each resource in hand
+    for give_idx, amount in enumerate(hand_freqdeck):
+        rate = rates[RESOURCES[give_idx]]
+        if amount >= rate:
+            # Try trading for each other resource the bank has
+            for receive_idx, bank_amount in enumerate(bank_freqdeck):
+                if receive_idx != give_idx and bank_amount > 0:
+                    # Create concatenated freqdeck [give_5 + receive_5]
+                    freqdeck = [0] * 10
+                    freqdeck[give_idx] = rate
+                    freqdeck[5 + receive_idx] = 1
+                    trade_offers.add(tuple(freqdeck))
 
     return trade_offers
diff --git a/catanatron_core/catanatron/state.py b/catanatron_core/catanatron/state.py
index 665eab8c..a12a343b 100644
--- a/catanatron_core/catanatron/state.py
+++ b/catanatron_core/catanatron/state.py
@@ -589,19 +589,24 @@ def apply_action(state: State, action: Action):
         state.current_prompt = ActionPrompt.PLAY_TURN
         state.playable_actions = generate_playable_actions(state)
     elif action.action_type == ActionType.MARITIME_TRADE:
-        trade_offer = action.value
-        offering = freqdeck_from_listdeck(
-            filter(lambda r: r is not None, trade_offer[:-1])
-        )
-        asking = freqdeck_from_listdeck(trade_offer[-1:])
-        if not player_resource_freqdeck_contains(state, action.color, offering):
+        # action.value is now a 10-length tuple of integers [give_5 + receive_5]
+        giving_freqdeck = list(action.value[:5])  # First 5 are resources given
+        receiving_freqdeck = list(action.value[5:])  # Last 5 are resources received
+
+        # Validate player has resources
+        if not player_resource_freqdeck_contains(state, action.color, giving_freqdeck):
             raise ValueError("Trying to trade without money")
-        if not freqdeck_contains(state.resource_freqdeck, asking):
-            raise ValueError("Bank doenst have those cards")
-        player_freqdeck_subtract(state, action.color, offering)
-        state.resource_freqdeck = freqdeck_add(state.resource_freqdeck, offering)
-        player_freqdeck_add(state, action.color, asking)
-        state.resource_freqdeck = freqdeck_subtract(state.resource_freqdeck, asking)
+        # Validate bank has resources
+        if not freqdeck_contains(state.resource_freqdeck, receiving_freqdeck):
+            raise ValueError("Bank doesn't have those cards")
+
+        # Execute trade
+        player_freqdeck_subtract(state, action.color, giving_freqdeck)
+        state.resource_freqdeck = freqdeck_add(state.resource_freqdeck, giving_freqdeck)
+        player_freqdeck_add(state, action.color, receiving_freqdeck)
+        state.resource_freqdeck = freqdeck_subtract(
+            state.resource_freqdeck, receiving_freqdeck
+        )
 
         # state.current_player_index stays the same
         state.current_prompt = ActionPrompt.PLAY_TURN
diff --git a/catanatron_gym/catanatron_gym/envs/catanatron_env.py b/catanatron_gym/catanatron_gym/envs/catanatron_env.py
index a5c76d03..a62653a7 100644
--- a/catanatron_gym/catanatron_gym/envs/catanatron_env.py
+++ b/catanatron_gym/catanatron_gym/envs/catanatron_env.py
@@ -20,14 +20,59 @@
 
 BASE_TOPOLOGY = BASE_MAP_TEMPLATE.topology
 TILE_COORDINATES = [x for x, y in BASE_TOPOLOGY.items() if y == LandTile]
+
+
+def generate_trade_actions():
+    """Generates all possible maritime trade actions in freqdeck format"""
+    trade_actions = []
+
+    # 4:1 trades
+    for give_resource in RESOURCES:
+        give_idx = RESOURCES.index(give_resource)
+        for receive_resource in RESOURCES:
+            if give_resource != receive_resource:
+                receive_idx = RESOURCES.index(receive_resource)
+                # Create 10-length freqdeck [giving_5 + receiving_5]
+                freqdeck = [0] * 10
+                freqdeck[give_idx] = 4  # Give 4 resources
+                freqdeck[5 + receive_idx] = 1  # Receive 1 resource
+                trade_actions.append((ActionType.MARITIME_TRADE, tuple(freqdeck)))
+
+    # 3:1 port trades
+    for give_resource in RESOURCES:
+        give_idx = RESOURCES.index(give_resource)
+        for receive_resource in RESOURCES:
+            if give_resource != receive_resource:
+                receive_idx = RESOURCES.index(receive_resource)
+                freqdeck = [0] * 10
+                freqdeck[give_idx] = 3  # Give 3 resources
+                freqdeck[5 + receive_idx] = 1  # Receive 1 resource
+                trade_actions.append((ActionType.MARITIME_TRADE, tuple(freqdeck)))
+
+    # 2:1 port trades
+    for give_resource in RESOURCES:
+        give_idx = RESOURCES.index(give_resource)
+        for receive_resource in RESOURCES:
+            if give_resource != receive_resource:
+                receive_idx = RESOURCES.index(receive_resource)
+                freqdeck = [0] * 10
+                freqdeck[give_idx] = 2  # Give 2 resources
+                freqdeck[5 + receive_idx] = 1  # Receive 1 resource
+                trade_actions.append((ActionType.MARITIME_TRADE, tuple(freqdeck)))
+
+    return trade_actions
+
+
 ACTIONS_ARRAY = [
     (ActionType.ROLL, None),
-    # TODO: One for each tile (and abuse 1v1 setting).
+    # Move robber actions
     *[(ActionType.MOVE_ROBBER, tile) for tile in TILE_COORDINATES],
     (ActionType.DISCARD, None),
+    # Build actions
     *[(ActionType.BUILD_ROAD, tuple(sorted(edge))) for edge in get_edges()],
     *[(ActionType.BUILD_SETTLEMENT, node_id) for node_id in range(NUM_NODES)],
     *[(ActionType.BUILD_CITY, node_id) for node_id in range(NUM_NODES)],
+    # Development card actions
     (ActionType.BUY_DEVELOPMENT_CARD, None),
     (ActionType.PLAY_KNIGHT_CARD, None),
     *[
@@ -38,27 +83,8 @@
     *[(ActionType.PLAY_YEAR_OF_PLENTY, (first_card,)) for first_card in RESOURCES],
     (ActionType.PLAY_ROAD_BUILDING, None),
     *[(ActionType.PLAY_MONOPOLY, r) for r in RESOURCES],
-    # 4:1 with bank
-    *[
-        (ActionType.MARITIME_TRADE, tuple(4 * [i] + [j]))
-        for i in RESOURCES
-        for j in RESOURCES
-        if i != j
-    ],
-    # 3:1 with port
-    *[
-        (ActionType.MARITIME_TRADE, tuple(3 * [i] + [None, j]))  # type: ignore
-        for i in RESOURCES
-        for j in RESOURCES
-        if i != j
-    ],
-    # 2:1 with port
-    *[
-        (ActionType.MARITIME_TRADE, tuple(2 * [i] + [None, None, j]))  # type: ignore
-        for i in RESOURCES
-        for j in RESOURCES
-        if i != j
-    ],
+    # Maritime trade actions
+    *generate_trade_actions(),
     (ActionType.END_TURN, None),
 ]
 ACTION_SPACE_SIZE = len(ACTIONS_ARRAY)
@@ -70,6 +96,7 @@ def to_action_type_space(action):
 
 
 def normalize_action(action):
+    """Normalize action value to ensure it can be found in ACTIONS_ARRAY"""
     normalized = action
     if normalized.action_type == ActionType.ROLL:
         return Action(action.color, action.action_type, None)
diff --git a/tests/test_gym.py b/tests/test_gym.py
index 472bce14..91a9f74d 100644
--- a/tests/test_gym.py
+++ b/tests/test_gym.py
@@ -126,7 +126,7 @@ def test_enemies():
 
     # Virtually impossible for a Random bot to beat Value Function Player
     assert env.game.winning_color() == Color.RED  # type: ignore
-    assert reward - 1
+    assert reward == -1
     env.close()
 
 
diff --git a/tests/test_state.py b/tests/test_state.py
index cb4414f8..5dc658d0 100644
--- a/tests/test_state.py
+++ b/tests/test_state.py
@@ -76,11 +76,21 @@ def test_trade_execution():
     state = State(players)
 
     player_deck_replenish(state, players[0].color, BRICK, 4)
-    trade_offer = tuple([BRICK] * 4 + [ORE])
-    action = Action(players[0].color, ActionType.MARITIME_TRADE, trade_offer)
+
+    # Create trade freqdeck
+    brick_idx = RESOURCES.index(BRICK)
+    ore_idx = RESOURCES.index(ORE)
+    give_freqdeck = [0] * 5
+    receive_freqdeck = [0] * 5
+    give_freqdeck[brick_idx] = 4  # Give 4 BRICK
+    receive_freqdeck[ore_idx] = 1  # Get 1 ORE
+    trade_freqdeck = tuple(give_freqdeck + receive_freqdeck)
+
+    action = Action(players[0].color, ActionType.MARITIME_TRADE, trade_freqdeck)
     apply_action(state, action)
 
-    assert player_num_resource_cards(state, players[0].color) == 1
+    assert player_num_resource_cards(state, players[0].color, BRICK) == 0
+    assert player_num_resource_cards(state, players[0].color, ORE) == 1
     assert sum(state.resource_freqdeck) == 19 * 5 + 4 - 1
 
 
diff --git a/ui/src/components/Prompt.js b/ui/src/components/Prompt.js
index d7eeab52..e3a3e80e 100644
--- a/ui/src/components/Prompt.js
+++ b/ui/src/components/Prompt.js
@@ -90,8 +90,29 @@ export function humanizeAction(gameState, action) {
 }
 
 export function humanizeTradeAction(action) {
-  const out = action[2].slice(0, 4).filter((resource) => resource !== null);
-  return `${out.length} ${out[0]} => ${action[2][4]}`;
+  const freqdeck = action[2];
+  const RESOURCES = ['WOOD', 'BRICK', 'SHEEP', 'WHEAT', 'ORE'];
+
+  const resourcesGiven = [];
+  const resourcesReceived = [];
+
+  // Parse resources given (indices 0-4)
+  for (let i = 0; i < 5; i++) {
+    const amount = freqdeck[i];
+    if (amount > 0) {
+      resourcesGiven.push(`${amount} ${RESOURCES[i]}`);
+    }
+  }
+
+  // Parse resources received (indices 5-9)
+  for (let i = 5; i < 10; i++) {
+    const amount = freqdeck[i];
+    if (amount > 0) {
+      resourcesReceived.push(`${amount} ${RESOURCES[i - 5]}`);
+    }
+  }
+
+  return `${resourcesGiven.join(', ')} => ${resourcesReceived.join(', ')}`;
 }
 
 function humanizePrompt(current_prompt) {