diff --git a/src/mudlib/commands/power.py b/src/mudlib/commands/power.py
new file mode 100644
index 0000000..ac60b57
--- /dev/null
+++ b/src/mudlib/commands/power.py
@@ -0,0 +1,211 @@
+"""Power commands for raising and lowering PL."""
+
+import asyncio
+
+from mudlib.combat.engine import get_encounter
+from mudlib.commands import CommandDefinition, register
+from mudlib.commands.movement import send_nearby_message
+from mudlib.gmcp import send_char_vitals
+from mudlib.player import Player
+
+# Power-up mechanics
+POWER_UP_TICK_INTERVAL = 0.05  # seconds between ticks
+POWER_UP_PL_PER_TICK = 5.0  # PL increase per tick
+POWER_UP_STAMINA_COST_PER_TICK = 2.0  # stamina cost per tick
+POWER_DOWN_MIN_PL = 1.0  # minimum PL when powering down
+
+
+async def power_up_loop(player: Player, target_pl: float | None = None) -> None:
+    """Background task that powers up the player over time.
+
+    Args:
+        player: The player powering up
+        target_pl: Optional target PL to stop at (defaults to max_pl)
+    """
+    target = target_pl if target_pl is not None else player.max_pl
+
+    try:
+        while player.pl < target and player.stamina > 0:
+            await asyncio.sleep(POWER_UP_TICK_INTERVAL)
+
+            # Deduct stamina
+            player.stamina -= POWER_UP_STAMINA_COST_PER_TICK
+            if player.stamina < 0:
+                player.stamina = 0.0
+
+            # Increase PL
+            old_pl = player.pl
+            player.pl = min(player.pl + POWER_UP_PL_PER_TICK, target)
+
+            # Send GMCP update
+            send_char_vitals(player)
+
+            # Send periodic aura message (every ~0.2s)
+            if int(old_pl / 20) != int(player.pl / 20):
+                await player.send("Your aura flares!\r\n")
+                await send_nearby_message(
+                    player, player.x, player.y, f"{player.name}'s aura flares!\r\n"
+                )
+
+            # Check if we've run out of stamina
+            if player.stamina <= 0:
+                await player.send("You run out of stamina and stop powering up.\r\n")
+                await send_nearby_message(
+                    player,
+                    player.x,
+                    player.y,
+                    f"{player.name} stops powering up.\r\n",
+                )
+                break
+
+        # Reached target
+        if player.pl >= target:
+            await player.send(f"You reach your target power level of {target}.\r\n")
+            await send_nearby_message(
+                player,
+                player.x,
+                player.y,
+                f"{player.name} reaches their target power level.\r\n",
+            )
+    finally:
+        # Clean up the task reference
+        player._power_task = None
+
+
+async def cmd_power(player: Player, args: str) -> None:
+    """Manage power level.
+
+    Usage:
+        power up - raise PL toward max_pl
+        power down - lower PL to minimum
+        power <number> - set PL to exact value
+        power stop - cancel ongoing power-up
+    """
+    if not args:
+        await player.send("Usage: power up|down|stop|<number>\r\n")
+        return
+
+    args = args.strip().lower()
+
+    # Handle power stop
+    if args == "stop":
+        if player._power_task is None or player._power_task.done():
+            await player.send("You're not powering up.\r\n")
+            return
+
+        player._power_task.cancel()
+        player._power_task = None
+        await player.send("You stop powering up.\r\n")
+        await send_nearby_message(
+            player, player.x, player.y, f"{player.name} stops powering up.\r\n"
+        )
+        return
+
+    # Handle power down
+    if args == "down":
+        # Cancel any ongoing power-up
+        if player._power_task is not None and not player._power_task.done():
+            player._power_task.cancel()
+            player._power_task = None
+
+        player.pl = POWER_DOWN_MIN_PL
+        send_char_vitals(player)
+        await player.send(f"You power down to PL {POWER_DOWN_MIN_PL}.\r\n")
+        await send_nearby_message(
+            player, player.x, player.y, f"{player.name} powers down.\r\n"
+        )
+        return
+
+    # Handle power up
+    if args == "up":
+        # Check if already powering up
+        if player._power_task is not None and not player._power_task.done():
+            await player.send("You're already powering up!\r\n")
+            return
+
+        # Check for combat
+        if get_encounter(player) is not None:
+            await player.send("You can't power up during combat!\r\n")
+            return
+
+        # Check stamina
+        if player.stamina <= 0:
+            await player.send("You don't have enough stamina to power up!\r\n")
+            return
+
+        # Check if already at max
+        if player.pl >= player.max_pl:
+            await player.send("You're already at maximum power!\r\n")
+            return
+
+        # Start power-up loop
+        await player.send("You begin powering up...\r\n")
+        await send_nearby_message(
+            player, player.x, player.y, f"{player.name} begins powering up!\r\n"
+        )
+        player._power_task = asyncio.create_task(power_up_loop(player))
+        return
+
+    # Handle power <number>
+    try:
+        target = float(args)
+    except ValueError:
+        await player.send(f"Invalid power level: {args}\r\n")
+        return
+
+    # Validate target
+    if target <= 0:
+        await player.send("Power level must be greater than 0.\r\n")
+        return
+
+    if target > player.max_pl:
+        await player.send(
+            f"Power level cannot exceed your maximum of {player.max_pl}.\r\n"
+        )
+        return
+
+    # If target is lower than current, instant change
+    if target < player.pl:
+        # Cancel any ongoing power-up
+        if player._power_task is not None and not player._power_task.done():
+            player._power_task.cancel()
+            player._power_task = None
+
+        player.pl = target
+        send_char_vitals(player)
+        await player.send(f"You lower your power to {target}.\r\n")
+        await send_nearby_message(
+            player, player.x, player.y, f"{player.name} lowers their power.\r\n"
+        )
+        return
+
+    # If target is higher, start power-up loop to that target
+    if target > player.pl:
+        # Check if already powering up
+        if player._power_task is not None and not player._power_task.done():
+            await player.send("You're already powering up!\r\n")
+            return
+
+        # Check for combat
+        if get_encounter(player) is not None:
+            await player.send("You can't power up during combat!\r\n")
+            return
+
+        # Check stamina
+        if player.stamina <= 0:
+            await player.send("You don't have enough stamina to power up!\r\n")
+            return
+
+        # Start power-up loop to target
+        await player.send(f"You begin powering up to {target}...\r\n")
+        await send_nearby_message(
+            player, player.x, player.y, f"{player.name} begins powering up!\r\n"
+        )
+        player._power_task = asyncio.create_task(power_up_loop(player, target))
+        return
+
+    # Target equals current PL
+    await player.send(f"You're already at PL {target}.\r\n")
+
+
+register(CommandDefinition("power", cmd_power, aliases=["pow"]))
diff --git a/src/mudlib/player.py b/src/mudlib/player.py
index 775dbf5..62a21cb 100644
--- a/src/mudlib/player.py
+++ b/src/mudlib/player.py
@@ -2,6 +2,7 @@
 
 from __future__ import annotations
 
+import asyncio
 from dataclasses import dataclass, field
 from typing import TYPE_CHECKING, Any
 
@@ -32,6 +33,7 @@ class Player(Entity):
     paint_brush: str = "."
     prompt_template: str | None = None
     _last_msdp: dict = field(default_factory=dict, repr=False)
+    _power_task: asyncio.Task | None = None
 
     @property
     def mode(self) -> str:
diff --git a/src/mudlib/server.py b/src/mudlib/server.py
index bce88dd..3a4dfc0 100644
--- a/src/mudlib/server.py
+++ b/src/mudlib/server.py
@@ -24,6 +24,7 @@ import mudlib.commands.look
 import mudlib.commands.movement
 import mudlib.commands.play
 import mudlib.commands.portals
+import mudlib.commands.power
 import mudlib.commands.quit
 import mudlib.commands.reload
 import mudlib.commands.spawn
diff --git a/tests/test_power.py b/tests/test_power.py
new file mode 100644
index 0000000..4a521ae
--- /dev/null
+++ b/tests/test_power.py
@@ -0,0 +1,309 @@
+"""Tests for power commands."""
+
+import asyncio
+import time
+from unittest.mock import AsyncMock, MagicMock
+
+import pytest
+
+from mudlib.combat.encounter import CombatEncounter
+from mudlib.combat.engine import active_encounters
+from mudlib.commands.power import cmd_power
+from mudlib.player import Player, players
+from mudlib.zone import Zone
+
+
+@pytest.fixture(autouse=True)
+def clear_state():
+    """Clear players and encounters before and after each test."""
+    players.clear()
+    active_encounters.clear()
+    yield
+    players.clear()
+    active_encounters.clear()
+
+
+@pytest.fixture
+def test_zone():
+    """Create a test zone for players."""
+    terrain = [["." for _ in range(256)] for _ in range(256)]
+    zone = Zone(
+        name="testzone",
+        width=256,
+        height=256,
+        toroidal=True,
+        terrain=terrain,
+        impassable=set(),
+    )
+    return zone
+
+
+@pytest.fixture
+def mock_writer():
+    writer = MagicMock()
+    writer.write = MagicMock()
+    writer.drain = AsyncMock()
+    return writer
+
+
+@pytest.fixture
+def mock_reader():
+    return MagicMock()
+
+
+@pytest.fixture
+def player(mock_reader, mock_writer, test_zone):
+    p = Player(name="Goku", x=0, y=0, reader=mock_reader, writer=mock_writer)
+    p.location = test_zone
+    test_zone._contents.append(p)
+    players[p.name] = p
+    return p
+
+
+@pytest.fixture
+def nearby_player(mock_reader, mock_writer, test_zone):
+    p = Player(name="Vegeta", x=0, y=0, reader=mock_reader, writer=mock_writer)
+    p.location = test_zone
+    test_zone._contents.append(p)
+    players[p.name] = p
+    return p
+
+
+@pytest.mark.asyncio
+async def test_power_down_instantly_lowers_pl(player):
+    """Test power down instantly lowers PL to minimum."""
+    player.pl = 100.0
+    player.max_pl = 100.0
+
+    await cmd_power(player, "down")
+
+    assert player.pl == 1.0
+    messages = [call[0][0] for call in player.writer.write.call_args_list]
+    assert any("power down" in msg.lower() for msg in messages)
+
+
+@pytest.mark.asyncio
+async def test_power_to_number_lowers_instantly(player):
+    """Test power <number> instantly lowers when target < current."""
+    player.pl = 100.0
+    player.max_pl = 100.0
+
+    await cmd_power(player, "50")
+
+    assert player.pl == 50.0
+    messages = [call[0][0] for call in player.writer.write.call_args_list]
+    assert any("50" in msg for msg in messages)
+
+
+@pytest.mark.asyncio
+async def test_power_to_number_rejects_zero(player):
+    """Test power <number> rejects 0 or negative values."""
+    player.pl = 100.0
+
+    await cmd_power(player, "0")
+
+    assert player.pl == 100.0  # unchanged
+    messages = [call[0][0] for call in player.writer.write.call_args_list]
+    assert any("must be greater than 0" in msg.lower() for msg in messages)
+
+
+@pytest.mark.asyncio
+async def test_power_to_number_rejects_above_max(player):
+    """Test power <number> rejects values above max_pl."""
+    player.pl = 100.0
+    player.max_pl = 100.0
+
+    await cmd_power(player, "150")
+
+    assert player.pl == 100.0  # unchanged
+    messages = [call[0][0] for call in player.writer.write.call_args_list]
+    assert any("maximum" in msg.lower() for msg in messages)
+
+
+@pytest.mark.asyncio
+async def test_power_up_starts_increasing_pl(player):
+    """Test power up starts a loop that increases PL over time."""
+    player.pl = 10.0
+    player.max_pl = 100.0
+    player.stamina = 100.0
+
+    await cmd_power(player, "up")
+
+    # Give it a moment to run a few ticks
+    await asyncio.sleep(0.15)
+
+    assert player.pl > 10.0
+    assert player.pl < player.max_pl
+
+
+@pytest.mark.asyncio
+async def test_power_up_deducts_stamina(player):
+    """Test power up deducts stamina per tick."""
+    player.pl = 10.0
+    player.max_pl = 100.0
+    player.stamina = 100.0
+
+    await cmd_power(player, "up")
+
+    # Give it a moment to run a few ticks
+    await asyncio.sleep(0.15)
+
+    assert player.stamina < 100.0
+
+
+@pytest.mark.asyncio
+async def test_power_up_stops_at_max_pl(player):
+    """Test power up stops when PL reaches max_pl."""
+    player.pl = 95.0
+    player.max_pl = 100.0
+    player.stamina = 100.0
+
+    await cmd_power(player, "up")
+
+    # Wait for it to complete
+    await asyncio.sleep(0.3)
+
+    assert player.pl == 100.0
+    assert player._power_task is None or player._power_task.done()
+
+
+@pytest.mark.asyncio
+async def test_power_up_stops_when_stamina_depleted(player):
+    """Test power up stops when stamina runs out."""
+    player.pl = 10.0
+    player.max_pl = 100.0
+    player.stamina = 5.0  # Very low stamina
+
+    await cmd_power(player, "up")
+
+    # Wait for stamina to deplete
+    await asyncio.sleep(0.3)
+
+    # PL should have increased a little, but stopped
+    assert player.pl > 10.0
+    assert player.pl < 100.0
+    assert player.stamina <= 0.0
+    assert player._power_task is None or player._power_task.done()
+
+
+@pytest.mark.asyncio
+async def test_power_stop_cancels_power_up(player):
+    """Test power stop cancels an ongoing power-up."""
+    player.pl = 10.0
+    player.max_pl = 100.0
+    player.stamina = 100.0
+
+    await cmd_power(player, "up")
+    await asyncio.sleep(0.05)  # Let it start
+
+    await cmd_power(player, "stop")
+
+    pl_at_stop = player.pl
+    await asyncio.sleep(0.1)  # Wait a bit more
+
+    # PL should not have increased after stop
+    assert player.pl == pl_at_stop
+    assert player._power_task is None or player._power_task.done()
+
+
+@pytest.mark.asyncio
+async def test_power_up_rejects_during_combat(player, nearby_player):
+    """Test power up is rejected when player is in combat."""
+    player.pl = 50.0
+    player.stamina = 100.0
+
+    # Put player in combat
+    encounter = CombatEncounter(
+        attacker=player, defender=nearby_player, last_action_at=time.monotonic()
+    )
+    active_encounters.append(encounter)
+
+    await cmd_power(player, "up")
+
+    messages = [call[0][0] for call in player.writer.write.call_args_list]
+    assert any("combat" in msg.lower() for msg in messages)
+    assert player.pl == 50.0  # unchanged
+
+
+@pytest.mark.asyncio
+async def test_power_up_rejects_with_no_stamina(player):
+    """Test power up is rejected when stamina is 0."""
+    player.pl = 50.0
+    player.stamina = 0.0
+
+    await cmd_power(player, "up")
+
+    messages = [call[0][0] for call in player.writer.write.call_args_list]
+    assert any("stamina" in msg.lower() for msg in messages)
+    assert player.pl == 50.0  # unchanged
+
+
+@pytest.mark.asyncio
+async def test_power_up_sends_feedback_messages(player):
+    """Test power up sends feedback to player."""
+    player.pl = 10.0
+    player.max_pl = 100.0
+    player.stamina = 100.0
+
+    await cmd_power(player, "up")
+
+    messages = [call[0][0] for call in player.writer.write.call_args_list]
+    assert any("powering up" in msg.lower() for msg in messages)
+
+
+@pytest.mark.asyncio
+async def test_power_up_broadcasts_to_nearby(player, nearby_player):
+    """Test power up broadcasts to nearby players."""
+    player.pl = 10.0
+    player.max_pl = 100.0
+    player.stamina = 100.0
+
+    await cmd_power(player, "up")
+
+    nearby_messages = [call[0][0] for call in nearby_player.writer.write.call_args_list]
+    assert any("Goku" in msg and "power" in msg.lower() for msg in nearby_messages)
+
+
+@pytest.mark.asyncio
+async def test_power_up_when_already_powering_up(player):
+    """Test power up when already powering up sends message."""
+    player.pl = 10.0
+    player.max_pl = 100.0
+    player.stamina = 100.0
+
+    await cmd_power(player, "up")
+    await asyncio.sleep(0.05)
+
+    # Try to power up again
+    await cmd_power(player, "up")
+
+    messages = [call[0][0] for call in player.writer.write.call_args_list]
+    assert any("already" in msg.lower() for msg in messages)
+
+
+@pytest.mark.asyncio
+async def test_power_down_broadcasts_to_nearby(player, nearby_player):
+    """Test power down broadcasts to nearby players."""
+    player.pl = 100.0
+
+    await cmd_power(player, "down")
+
+    nearby_messages = [call[0][0] for call in nearby_player.writer.write.call_args_list]
+    assert any("Goku" in msg and "power" in msg.lower() for msg in nearby_messages)
+
+
+@pytest.mark.asyncio
+async def test_power_to_number_raises_with_loop(player):
+    """Test power <number> starts power-up loop when target > current."""
+    player.pl = 10.0
+    player.max_pl = 100.0
+    player.stamina = 100.0
+
+    await cmd_power(player, "80")
+
+    # Give it a moment to run
+    await asyncio.sleep(0.15)
+
+    # Should be increasing toward 80
+    assert player.pl > 10.0
+    assert player.stamina < 100.0  # deducting stamina