diff --git a/api/unitframes.lua b/api/unitframes.lua
index 1c66af91..7edbd6da 100644
--- a/api/unitframes.lua
+++ b/api/unitframes.lua
@@ -247,7 +247,7 @@ end)
 -- GetUnitStats - Nampower Integration for Health + Power
 -- Returns: hp, maxHp, power, maxPower, powerType
 -- IMPORTANT: Uses _G.UnitExists directly to avoid conflicts with Nampower's
---            extended UnitExists that returns (exists, guid)
+--            use GetUnitGUID(unit) for GUID lookup (Nampower 3.0.0+)
 -- ============================================================================
 
 -- Cache für Stats-Tracking (nur Änderungen zählen)
@@ -1168,7 +1168,7 @@ function pfUI.uf.OnEvent()
     -- Smart update: check if THIS frame's unit actually changed
     if pfUI.uf.guidTracker and this.id then
       local unit = this.label == "player" and "player" or (this.label .. this.id)
-      local _, newGuid = UnitExists(unit)
+      local newGuid = GetUnitGUID(unit)
       local oldGuid = pfUI.uf.guidTracker.frameToGuid[this]
       if newGuid ~= oldGuid then
         pfUI.uf.guidTracker.frameToGuid[this] = newGuid
@@ -1455,7 +1455,7 @@ function pfUI.uf.OnUpdate()
         -- O(1) Nampower lookup via GUID (same pattern as nameplates.lua)
         local health, maxHealth
         if GetUnitField then
-          local _, guid = UnitExists(unit)
+          local guid = GetUnitGUID(unit)
           if guid then
             health = GetUnitField(guid, "health")
             maxHealth = GetUnitField(guid, "maxHealth")
@@ -3288,7 +3288,7 @@ function pfUI.uf.GetColor(self, preset)
     -- O(1) Nampower lookup for health gradient color
     local hp, hpmax
     if GetUnitField then
-      local _, guid = UnitExists(unitstr)
+      local guid = GetUnitGUID(unitstr)
       if guid then
         hp = GetUnitField(guid, "health")
         hpmax = GetUnitField(guid, "maxHealth")
diff --git a/libs/libcast.lua b/libs/libcast.lua
index 2c148dad..cb9a49b8 100644
--- a/libs/libcast.lua
+++ b/libs/libcast.lua
@@ -68,7 +68,7 @@ UnitChannelInfo = function(unit)
     guid = unit  -- unit IS the GUID
   elseif pfValidUnits[unit] and UnitExists then
     -- unit is a token like "target" - get GUID from it
-    local _, unitGuid = UnitExists(unit)
+    local unitGuid = GetUnitGUID(unit)
     guid = unitGuid
   end
   
@@ -167,7 +167,7 @@ UnitCastingInfo = function(unit)
     guid = unit  -- unit IS the GUID
   elseif pfValidUnits[unit] and UnitExists then
     -- unit is a token like "target" - get GUID from it
-    local _, unitGuid = UnitExists(unit)
+    local unitGuid = GetUnitGUID(unit)
     guid = unitGuid
   end
   
diff --git a/libs/libdebuff.lua b/libs/libdebuff.lua
index 9bd22e37..676a75f6 100644
--- a/libs/libdebuff.lua
+++ b/libs/libdebuff.lua
@@ -38,7 +38,7 @@ local hasNampower = false
 if GetNampowerVersion then
   local major, minor, patch = GetNampowerVersion()
   patch = patch or 0
-  -- Minimum required version: 2.41.0 (CastSpellByName unitStr support, SetMouseoverUnit)
+  -- Minimum required version: 3.0.0 (GetUnitGUID support)
   if major > 2 or (major == 2 and minor > 41) or (major == 2 and minor == 41 and patch >= 0) then
     hasNampower = true
   end
@@ -101,7 +101,7 @@ nampowerCheckFrame:SetScript("OnEvent", function()
         end
 
       else
-        DEFAULT_CHAT_FRAME:AddMessage("|cffff0000[libdebuff] Debuff tracking disabled! Please update Nampower to v2.41.0 or higher.|r")
+        DEFAULT_CHAT_FRAME:AddMessage("|cffff0000[libdebuff] Debuff tracking disabled! Please update Nampower to v3.0.0 or higher.|r")
         StaticPopup_Show("LIBDEBUFF_NAMPOWER_UPDATE", versionString)
       end
     else
@@ -217,7 +217,7 @@ pfUI.libpredict_pending_cast = pfUI.libpredict_pending_cast or {}
 -- ============================================================================
 
 StaticPopupDialogs["LIBDEBUFF_NAMPOWER_UPDATE"] = {
-  text = "|cffff0000!!!WARNING!!!|r\n\nNampower Update Required!\n\nYour current version: %s\nRequired version: 2.41.0+\n\nPlease update Nampower to continue using pfUI!",
+  text = "|cffff0000!!!WARNING!!!|r\n\nNampower Update Required!\n\nYour current version: %s\nRequired version: 3.0.0+\n\nPlease update Nampower to continue using pfUI!",
   button1 = "Show Download",
   button2 = "Dismiss",
   timeout = 0,
@@ -225,12 +225,12 @@ StaticPopupDialogs["LIBDEBUFF_NAMPOWER_UPDATE"] = {
   hideOnEscape = 0,
   preferredIndex = 3,
   OnAccept = function()
-    pfUI.chat.urlcopy.CopyText("https://gitea.com/avitasia/nampower/releases/tag/v2.41.0")
+    pfUI.chat.urlcopy.CopyText("https://gitea.com/avitasia/nampower/releases/tag/v3.0.0")
   end,
 }
 
 StaticPopupDialogs["LIBDEBUFF_NAMPOWER_MISSING"] = {
-  text = "|cffff0000!!!WARNING!!!|r\n\nNampower Not Found!\n\nNampower 2.41.0+ is required for pfUI to function correctly.\n\nPlease install Nampower!",
+  text = "|cffff0000!!!WARNING!!!|r\n\nNampower Not Found!\n\nNampower 3.0.0+ is required for pfUI to function correctly.\n\nPlease install Nampower!",
   button1 = "Show Download",
   button2 = "Dismiss",
   timeout = 0,
@@ -315,8 +315,8 @@ end
 -- Player GUID Cache
 local playerGUID = nil
 local function GetPlayerGUID()
-  if not playerGUID and UnitExists then
-    local _, guid = UnitExists("player")
+  if not playerGUID and GetUnitGUID then
+    local guid = GetUnitGUID("player")
     playerGUID = guid
   end
   return playerGUID
@@ -344,8 +344,8 @@ end
 
 local function IsCurrentTarget(guid)
   if debugStats.trackAllUnits then return true end
-  if not guid or not UnitExists then return false end
-  local _, targetGuid = UnitExists("target")
+  if not guid or not GetUnitGUID then return false end
+  local targetGuid = GetUnitGUID("target")
   return targetGuid == guid
 end
 
@@ -834,8 +834,8 @@ function libdebuff:UnitDebuff(unit, displaySlot)
   local dtype = nil
 
   -- Nampower: Use GetUnitField for ALL debuff data (no Blizzard UnitDebuff needed)
-  if hasNampower and UnitExists then
-    local _, guid = UnitExists(unit)
+  if hasNampower and GetUnitGUID then
+    local guid = GetUnitGUID(unit)
     if not guid then
       -- Safety fallback: no GUID available (should not happen with Nampower)
       local bTexture, bStacks, bDtype = UnitDebuff(unit, displaySlot)
@@ -957,8 +957,8 @@ local _ownDebuffSortFunc = function(a, b)
 end
 
 function libdebuff:UnitOwnDebuff(unit, id)
-  if hasNampower and UnitExists then
-    local _, guid = UnitExists(unit)
+  if hasNampower and GetUnitGUID then
+    local guid = GetUnitGUID(unit)
     if guid and ownDebuffs[guid] then
       -- Build sorted list of our active debuffs
       local sortedDebuffs = {}
@@ -1143,8 +1143,8 @@ if hasNampower then
       end
       
       -- Trigger UI updates
-      if pfTarget and UnitExists("target") then
-        local _, currentTargetGuid = UnitExists("target")
+      if pfTarget and GetUnitGUID("target") then
+        local currentTargetGuid = GetUnitGUID("target")
         if currentTargetGuid == guid then
           pfTarget.update_aura = true
         end
@@ -1586,16 +1586,16 @@ if hasNampower then
         
         -- Notify unitframes of debuff updates (UNIT_AURA doesn't fire on refreshes!)
         -- Check player
-        if UnitExists("player") then
-          local _, playerGuid = UnitExists("player")
+        if GetUnitGUID("player") then
+          local playerGuid = GetUnitGUID("player")
           if playerGuid == targetGuid and pfPlayer then
             pfPlayer.update_aura = true
           end
         end
         
         -- Check target
-        if UnitExists("target") then
-          local _, targetUnitGuid = UnitExists("target")
+        if GetUnitGUID("target") then
+          local targetUnitGuid = GetUnitGUID("target")
           if targetUnitGuid == targetGuid and pfTarget then
             pfTarget.update_aura = true
           end
@@ -1899,8 +1899,8 @@ if hasNampower then
       end
 
     elseif event == "PLAYER_TARGET_CHANGED" then
-      if not UnitExists then return end
-      local _, targetGuid = UnitExists("target")
+      if not GetUnitGUID then return end
+      local targetGuid = GetUnitGUID("target")
       
       if targetGuid and targetGuid ~= "" then
         -- Invalidate slot map cache on retarget
@@ -1963,12 +1963,12 @@ _G.SlashCmdList["LIBDEBUGSTATS"] = function(msg)
     DEFAULT_CHAT_FRAME:AddMessage("|cff00ff00No manual slot shifting needed!|r")
     
   elseif msg == "target" then
-    if not UnitExists("target") then
+    if not GetUnitGUID("target") then
       DEFAULT_CHAT_FRAME:AddMessage("|cffff0000[libdebuff]|r No target!")
       return
     end
     
-    local _, guid = UnitExists("target")
+    local guid = GetUnitGUID("target")
     DEFAULT_CHAT_FRAME:AddMessage("|cff00ffff=== TARGET DEBUFF STATE ===|r")
     DEFAULT_CHAT_FRAME:AddMessage(string.format("GUID: %s", tostring(guid)))
     
diff --git a/libs/libpredict.lua b/libs/libpredict.lua
index 755d4cf9..590a0aa9 100644
--- a/libs/libpredict.lua
+++ b/libs/libpredict.lua
@@ -140,39 +140,33 @@ libpredict:SetScript("OnEvent", function()
   end
 end)
 
--- GUID->Name cache for dead players (UnitExists returns nil for corpses)
+-- GUID->Name cache for dead players (UnitExists/GetUnitGUID return nil for corpses)
 local guidNameCache = {}  -- [guid] = name
 
 local function resolveNameFromGuid(guid)
   if not guid then return nil end
   if guidNameCache[guid] then return guidNameCache[guid] end
-  local unit = UnitExists(guid)
-  local name = unit and type(unit) == "string" and UnitName(unit) or nil
-  if name then guidNameCache[guid] = name end
-  return name
+  -- UnitExists(guid) reverse lookup not reliable; cache is primary source
+  return nil
 end
 
 -- Register with libdebuff hooks
 local function cacheRaidNames()
-  -- Alle Raid/Party Mitglieder cachen solange sie noch auffindbar sind
+  -- Cache all raid/party members while they are still reachable
   for i = 1, GetNumRaidMembers() do
     local unit = "raid" .. i
-    if UnitExists(unit) then
-      local _, guid = UnitExists(unit)
-      local name = UnitName(unit)
-      if guid and name then guidNameCache[guid] = name end
-    end
+    local guid = GetUnitGUID(unit)
+    local name = UnitName(unit)
+    if guid and name then guidNameCache[guid] = name end
   end
   for i = 1, GetNumPartyMembers() do
     local unit = "party" .. i
-    if UnitExists(unit) then
-      local _, guid = UnitExists(unit)
-      local name = UnitName(unit)
-      if guid and name then guidNameCache[guid] = name end
-    end
+    local guid = GetUnitGUID(unit)
+    local name = UnitName(unit)
+    if guid and name then guidNameCache[guid] = name end
   end
-  -- Spieler selbst
-  local _, pguid = UnitExists("player")
+  -- player self
+  local pguid = GetUnitGUID("player")
   if pguid then guidNameCache[pguid] = UnitName("player") end
 end
 
@@ -478,8 +472,7 @@ function libpredict:ParseChatMessage(sender, msg, comm)
       for i = 1, GetNumRaidMembers() do
         local unit = "raid" .. i
         if UnitName(unit) == sender then
-          local _, guid = UnitExists(unit)
-          senderGuid = guid
+          senderGuid = GetUnitGUID(unit)
           break
         end
       end
@@ -487,8 +480,7 @@ function libpredict:ParseChatMessage(sender, msg, comm)
         for i = 1, GetNumPartyMembers() do
           local unit = "party" .. i
           if UnitName(unit) == sender then
-            local _, guid = UnitExists(unit)
-            senderGuid = guid
+            senderGuid = GetUnitGUID(unit)
             break
           end
         end
@@ -1173,7 +1165,7 @@ function libpredict:GetHotDuration(unit, spell)
   
   -- NEW: Try libdebuff first (Nampower AURA_CAST events)
   if pfUI.api.libdebuff and pfUI.api.libdebuff.GetBestAuraCast then
-    local _, guid = UnitExists(unit)  -- FIX: Get GUID, not exists boolean!
+    local guid = GetUnitGUID(unit)
     if guid then
       -- Get the best (highest rank) aura cast for this spell
       local spellName = spell
diff --git a/modules/actionbar.lua b/modules/actionbar.lua
index b7577957..02384ed7 100644
--- a/modules/actionbar.lua
+++ b/modules/actionbar.lua
@@ -1007,7 +1007,7 @@ pfUI:RegisterModule("actionbar", "vanilla", function ()
       -- Prowl Spell IDs: 5215 (Rank 1), 6783 (Rank 2), 9913 (Rank 3)
       if event == "UNIT_CASTEVENT" then
         local guid, target, cEvent, spellId = arg1, arg2, arg3, arg4
-        local _, playerGuid = UnitExists("player")
+        local playerGuid = GetUnitGUID("player")
         if guid == playerGuid and cEvent == "CAST" then
           if spellId == 5215 or spellId == 6783 or spellId == 9913 then
             -- Prowl cast detected
diff --git a/modules/castbar.lua b/modules/castbar.lua
index 8bac67fb..f8bdd99d 100644
--- a/modules/castbar.lua
+++ b/modules/castbar.lua
@@ -8,8 +8,8 @@ pfUI:RegisterModule("castbar", "vanilla", function ()
   -- Helper function for castbar timer formatting
   local function FormatCastbarTime(value)
     if C.unitframes.castbardecimals == "1" then
-      -- 1 decimal, always floor
-      return string.format("%.1f", floor(value * 10) / 10)
+      -- 1 decimal, round half up (matches Blizzard spellbook display)
+      return string.format("%.1f", floor(value * 10 + 0.5) / 10)
     else
       -- 2 decimals (default)
       return string.format("%.2f", value)
@@ -108,7 +108,7 @@ pfUI:RegisterModule("castbar", "vanilla", function ()
       if this.unitstr and string.find(this.unitstr, "^0x") then
         focusGuid = this.unitstr
       elseif this.unitstr and this.unitstr ~= "player" then
-        local _, guid = UnitExists(this.unitstr)
+        local guid = GetUnitGUID(this.unitstr)
         if guid then focusGuid = guid end
       end
 
@@ -176,7 +176,7 @@ pfUI:RegisterModule("castbar", "vanilla", function ()
             if pfUI.libdebuff_casts or pfUI.libdebuff_item_icons then
               local castGuid = nil
               if this.unitstr and UnitExists then
-                local _, guid = UnitExists(this.unitstr)
+                local guid = GetUnitGUID(this.unitstr)
                 castGuid = guid
               end
               if castGuid then
diff --git a/modules/focus.lua b/modules/focus.lua
index 55e42012..f36de44a 100644
--- a/modules/focus.lua
+++ b/modules/focus.lua
@@ -51,7 +51,7 @@ function SlashCmdList.PFFOCUS(msg)
   if msg ~= "" then
     -- Try to resolve GUID via short target swap
     if UnitExists then
-      local _, prevGUID = UnitExists("target")
+      local prevGUID = GetUnitGUID("target")
       local prevPlayer = UnitIsUnit("target", "player")
 
       -- Suppress "Unknown unit" errors during targeting attempts (fired async)
@@ -59,7 +59,7 @@ function SlashCmdList.PFFOCUS(msg)
 
       -- Try exact match first, then prefix match via /tar
       TargetByName(msg, true)
-      local _, guid = UnitExists("target")
+      local guid = GetUnitGUID("target")
 
       if not guid or guid == "0x0000000000000000" then
         -- Fallback: prefix match (like /tar storm -> Stormwind Guard)
@@ -94,7 +94,7 @@ function SlashCmdList.PFFOCUS(msg)
   else
     -- No msg: use current target
     if UnitExists then
-      local _, guid = UnitExists("target")
+      local guid = GetUnitGUID("target")
       if guid and guid ~= "0x0000000000000000" then
         SetFocusByGUID(guid)
         return
@@ -143,11 +143,11 @@ function SlashCmdList.PFCASTFOCUS(msg)
 
   -- For lua functions with GUID: short target swap via GUID
   if hasGUID and func then
-    local _, currentGUID = UnitExists("target")
+    local currentGUID = GetUnitGUID("target")
     local isPlayer = UnitIsUnit("target", "player")
 
     TargetUnit(focusGUID)
-    local _, newGUID = UnitExists("target")
+    local newGUID = GetUnitGUID("target")
 
     if newGUID ~= focusGUID then
       -- Could not target focus, restore and fail
diff --git a/modules/nameplates.lua b/modules/nameplates.lua
index 0a167028..760c05d9 100644
--- a/modules/nameplates.lua
+++ b/modules/nameplates.lua
@@ -101,7 +101,7 @@ pfUI:RegisterModule("nameplates", "vanilla", function ()
   local wipe = wipe or function(t) for k in pairs(t) do t[k] = nil end end
 
   -- Player GUID for filtering
-  local _, PlayerGUID = UnitExists("player")
+  local PlayerGUID = GetUnitGUID("player")
 
   -- ============================================================================
   -- OPTIMIZATION: Config caching
@@ -549,7 +549,7 @@ nameplates:RegisterEvent("ZONE_CHANGED_NEW_AREA")
 
     elseif event == "PLAYER_TARGET_CHANGED" then
       -- Flag target plate for update via GUID registry
-      local _, targetGuid = UnitExists("target")
+      local targetGuid = GetUnitGUID("target")
       if targetGuid then
         local plate = guidRegistry[targetGuid]
         if plate and plate.nameplate then
@@ -561,7 +561,7 @@ nameplates:RegisterEvent("ZONE_CHANGED_NEW_AREA")
 
     elseif event == "PLAYER_COMBO_POINTS" or event == "UNIT_COMBO_POINTS" then
       -- Only flag the target plate for combo point update
-      local _, targetGuid = UnitExists("target")
+      local targetGuid = GetUnitGUID("target")
       if targetGuid then
         local plate = guidRegistry[targetGuid]
         if plate and plate.nameplate then
@@ -1504,7 +1504,7 @@ nameplates:RegisterEvent("ZONE_CHANGED_NEW_AREA")
       if isTargetPlate then
         targetGUID = state and state.targetGuid
         if not targetGUID then
-          local _, guid = UnitExists("target")
+          local guid = GetUnitGUID("target")
           targetGUID = guid
         end
       end
@@ -1571,7 +1571,7 @@ nameplates:RegisterEvent("ZONE_CHANGED_NEW_AREA")
             channel, nameSubtext, text, texture, startTime, endTime, isTradeSkill = UnitChannelInfo("target")
           end
         elseif unitstr then
-          local _, guid = UnitExists(unitstr)
+          local guid = GetUnitGUID(unitstr)
           local q = guid or unitstr
           cast, nameSubtext, text, texture, startTime, endTime, isTradeSkill = UnitCastingInfo(q)
           if not cast then
diff --git a/modules/nampower.lua b/modules/nampower.lua
index e841cd4c..d6374e83 100644
--- a/modules/nampower.lua
+++ b/modules/nampower.lua
@@ -591,7 +591,7 @@ pfUI:RegisterModule("nampower", "vanilla", function ()
 
       -- Get base mana using Nampower's GetUnitField
       local baseMana, baseMaxMana
-      local _, guid = UnitExists(unit)
+      local guid = GetUnitGUID(unit)
 
       if guid then
         baseMana = GetUnitField(guid, "power1")
diff --git a/modules/raid.lua b/modules/raid.lua
index af45fe12..a389611c 100644
--- a/modules/raid.lua
+++ b/modules/raid.lua
@@ -121,7 +121,7 @@ pfUI:RegisterModule("raid", "vanilla:tbc", function ()
         local frame = pfUI.uf.raid[i]
         if frame and frame.id and frame.id > 0 then
           local unit = "raid" .. frame.id
-          local _, newGuid = UnitExists(unit)
+          local newGuid = GetUnitGUID(unit)
           local oldGuid = tracker.frameToGuid[frame]
           
           if newGuid ~= oldGuid then
diff --git a/modules/superwow.lua b/modules/superwow.lua
index 5d06f189..d3afd68b 100644
--- a/modules/superwow.lua
+++ b/modules/superwow.lua
@@ -266,7 +266,7 @@ pfUI:RegisterModule("superwow", "vanilla", function ()
     if event == "PLAYER_ENTERING_WORLD" then
       -- Cache player GUID
       if UnitExists then
-        local _, guid = UnitExists("player")
+        local guid = GetUnitGUID("player")
         playerGuid = guid
       end
       return
diff --git a/modules/swingtimer.lua b/modules/swingtimer.lua
index a4ac86b0..3788d647 100644
--- a/modules/swingtimer.lua
+++ b/modules/swingtimer.lua
@@ -575,7 +575,7 @@ pfUI:RegisterModule("swingtimer", "vanilla:tbc", function ()
     elseif event == "PLAYER_ENTERING_WORLD" then
       local _, class = UnitClass("player")
       isWarrior  = (class == "WARRIOR")
-      local _, guid = UnitExists("player")
+      local guid = GetUnitGUID("player")
       playerGUID = guid
       UpdateWeaponSpeeds()
       RebuildQueueSlotCache()