diff --git a/server/channelserver/handlers_guild_alliance.go b/server/channelserver/handlers_guild_alliance.go
index 53c0db800..f90607ae5 100644
--- a/server/channelserver/handlers_guild_alliance.go
+++ b/server/channelserver/handlers_guild_alliance.go
@@ -41,10 +41,20 @@ func handleMsgMhfOperateJoint(s *Session, p mhfpacket.MHFPacket) {
 	if err != nil {
 		s.logger.Error("Failed to get guild info", zap.Error(err))
 	}
+	if guild == nil {
+		s.logger.Error("Guild not found for alliance operation", zap.Uint32("GuildID", pkt.GuildID))
+		doAckSimpleFail(s, pkt.AckHandle, make([]byte, 4))
+		return
+	}
 	alliance, err := s.server.guildRepo.GetAllianceByID(pkt.AllianceID)
 	if err != nil {
 		s.logger.Error("Failed to get alliance info", zap.Error(err))
 	}
+	if alliance == nil {
+		s.logger.Error("Alliance not found for operation", zap.Uint32("AllianceID", pkt.AllianceID))
+		doAckSimpleFail(s, pkt.AckHandle, make([]byte, 4))
+		return
+	}
 
 	switch pkt.Action {
 	case mhfpacket.OPERATE_JOINT_DISBAND:
@@ -119,45 +129,45 @@ func handleMsgMhfInfoJoint(s *Session, p mhfpacket.MHFPacket) {
 	pkt := p.(*mhfpacket.MsgMhfInfoJoint)
 	bf := byteframe.NewByteFrame()
 	alliance, err := s.server.guildRepo.GetAllianceByID(pkt.AllianceID)
-	if err != nil {
+	if err != nil || alliance == nil {
 		doAckSimpleFail(s, pkt.AckHandle, make([]byte, 4))
-	} else {
-		bf.WriteUint32(alliance.ID)
-		bf.WriteUint32(uint32(alliance.CreatedAt.Unix()))
-		bf.WriteUint16(alliance.TotalMembers)
-		bf.WriteUint16(0x0000) // Unk
-		ps.Uint16(bf, alliance.Name, true)
-		if alliance.SubGuild1ID > 0 {
-			if alliance.SubGuild2ID > 0 {
-				bf.WriteUint8(3)
-			} else {
-				bf.WriteUint8(2)
-			}
-		} else {
-			bf.WriteUint8(1)
-		}
-		bf.WriteUint32(alliance.ParentGuildID)
-		bf.WriteUint32(alliance.ParentGuild.LeaderCharID)
-		bf.WriteUint16(alliance.ParentGuild.Rank(s.server.erupeConfig.RealClientMode))
-		bf.WriteUint16(alliance.ParentGuild.MemberCount)
-		ps.Uint16(bf, alliance.ParentGuild.Name, true)
-		ps.Uint16(bf, alliance.ParentGuild.LeaderName, true)
-		if alliance.SubGuild1ID > 0 {
-			bf.WriteUint32(alliance.SubGuild1ID)
-			bf.WriteUint32(alliance.SubGuild1.LeaderCharID)
-			bf.WriteUint16(alliance.SubGuild1.Rank(s.server.erupeConfig.RealClientMode))
-			bf.WriteUint16(alliance.SubGuild1.MemberCount)
-			ps.Uint16(bf, alliance.SubGuild1.Name, true)
-			ps.Uint16(bf, alliance.SubGuild1.LeaderName, true)
-		}
-		if alliance.SubGuild2ID > 0 {
-			bf.WriteUint32(alliance.SubGuild2ID)
-			bf.WriteUint32(alliance.SubGuild2.LeaderCharID)
-			bf.WriteUint16(alliance.SubGuild2.Rank(s.server.erupeConfig.RealClientMode))
-			bf.WriteUint16(alliance.SubGuild2.MemberCount)
-			ps.Uint16(bf, alliance.SubGuild2.Name, true)
-			ps.Uint16(bf, alliance.SubGuild2.LeaderName, true)
-		}
-		doAckBufSucceed(s, pkt.AckHandle, bf.Data())
+		return
 	}
+	bf.WriteUint32(alliance.ID)
+	bf.WriteUint32(uint32(alliance.CreatedAt.Unix()))
+	bf.WriteUint16(alliance.TotalMembers)
+	bf.WriteUint16(0x0000) // Unk
+	ps.Uint16(bf, alliance.Name, true)
+	if alliance.SubGuild1ID > 0 {
+		if alliance.SubGuild2ID > 0 {
+			bf.WriteUint8(3)
+		} else {
+			bf.WriteUint8(2)
+		}
+	} else {
+		bf.WriteUint8(1)
+	}
+	bf.WriteUint32(alliance.ParentGuildID)
+	bf.WriteUint32(alliance.ParentGuild.LeaderCharID)
+	bf.WriteUint16(alliance.ParentGuild.Rank(s.server.erupeConfig.RealClientMode))
+	bf.WriteUint16(alliance.ParentGuild.MemberCount)
+	ps.Uint16(bf, alliance.ParentGuild.Name, true)
+	ps.Uint16(bf, alliance.ParentGuild.LeaderName, true)
+	if alliance.SubGuild1ID > 0 {
+		bf.WriteUint32(alliance.SubGuild1ID)
+		bf.WriteUint32(alliance.SubGuild1.LeaderCharID)
+		bf.WriteUint16(alliance.SubGuild1.Rank(s.server.erupeConfig.RealClientMode))
+		bf.WriteUint16(alliance.SubGuild1.MemberCount)
+		ps.Uint16(bf, alliance.SubGuild1.Name, true)
+		ps.Uint16(bf, alliance.SubGuild1.LeaderName, true)
+	}
+	if alliance.SubGuild2ID > 0 {
+		bf.WriteUint32(alliance.SubGuild2ID)
+		bf.WriteUint32(alliance.SubGuild2.LeaderCharID)
+		bf.WriteUint16(alliance.SubGuild2.Rank(s.server.erupeConfig.RealClientMode))
+		bf.WriteUint16(alliance.SubGuild2.MemberCount)
+		ps.Uint16(bf, alliance.SubGuild2.Name, true)
+		ps.Uint16(bf, alliance.SubGuild2.LeaderName, true)
+	}
+	doAckBufSucceed(s, pkt.AckHandle, bf.Data())
 }
diff --git a/server/channelserver/handlers_guild_alliance_test.go b/server/channelserver/handlers_guild_alliance_test.go
index 0e483d6b8..fd40169b5 100644
--- a/server/channelserver/handlers_guild_alliance_test.go
+++ b/server/channelserver/handlers_guild_alliance_test.go
@@ -438,3 +438,70 @@ func TestInfoJoint_NotFound(t *testing.T) {
 		t.Error("No response packet queued")
 	}
 }
+
+func TestInfoJoint_NilAlliance(t *testing.T) {
+	server := createMockServer()
+	// alliance is nil, no error — simulates deleted alliance
+	guildMock := &mockGuildRepo{}
+	server.guildRepo = guildMock
+	session := createMockSession(1, server)
+
+	pkt := &mhfpacket.MsgMhfInfoJoint{AckHandle: 100, AllianceID: 999}
+
+	handleMsgMhfInfoJoint(session, pkt)
+
+	select {
+	case <-session.sendPackets:
+	default:
+		t.Error("No response packet queued — would softlock the client")
+	}
+}
+
+func TestOperateJoint_NilGuild(t *testing.T) {
+	server := createMockServer()
+	// guild is nil — simulates deleted guild
+	guildMock := &mockGuildRepo{
+		alliance: &GuildAlliance{ID: 5, ParentGuildID: 10},
+	}
+	server.guildRepo = guildMock
+	session := createMockSession(1, server)
+
+	pkt := &mhfpacket.MsgMhfOperateJoint{
+		AckHandle:  100,
+		AllianceID: 5,
+		GuildID:    10,
+		Action:     mhfpacket.OPERATE_JOINT_DISBAND,
+	}
+
+	handleMsgMhfOperateJoint(session, pkt)
+
+	select {
+	case <-session.sendPackets:
+	default:
+		t.Error("No response packet queued — would softlock the client")
+	}
+}
+
+func TestOperateJoint_NilAlliance(t *testing.T) {
+	server := createMockServer()
+	guildMock := &mockGuildRepo{}
+	guildMock.guild = &Guild{ID: 10}
+	guildMock.guild.LeaderCharID = 1
+	server.guildRepo = guildMock
+	session := createMockSession(1, server)
+
+	pkt := &mhfpacket.MsgMhfOperateJoint{
+		AckHandle:  100,
+		AllianceID: 999,
+		GuildID:    10,
+		Action:     mhfpacket.OPERATE_JOINT_DISBAND,
+	}
+
+	handleMsgMhfOperateJoint(session, pkt)
+
+	select {
+	case <-session.sendPackets:
+	default:
+		t.Error("No response packet queued — would softlock the client")
+	}
+}
diff --git a/server/channelserver/handlers_guild_info.go b/server/channelserver/handlers_guild_info.go
index 2153a2d08..dc7dc8182 100644
--- a/server/channelserver/handlers_guild_info.go
+++ b/server/channelserver/handlers_guild_info.go
@@ -135,8 +135,8 @@ func handleMsgMhfInfoGuild(s *Session, p mhfpacket.MHFPacket) {
 
 		if guild.AllianceID > 0 {
 			alliance, err := s.server.guildRepo.GetAllianceByID(guild.AllianceID)
-			if err != nil {
-				bf.WriteUint32(0) // Error, no alliance
+			if err != nil || alliance == nil {
+				bf.WriteUint32(0) // Error or missing alliance
 			} else {
 				bf.WriteUint32(alliance.ID)
 				bf.WriteUint32(uint32(alliance.CreatedAt.Unix()))
diff --git a/server/channelserver/repo_guild_alliance.go b/server/channelserver/repo_guild_alliance.go
index 744394a07..0b47e7549 100644
--- a/server/channelserver/repo_guild_alliance.go
+++ b/server/channelserver/repo_guild_alliance.go
@@ -97,6 +97,9 @@ func (r *GuildRepository) scanAllianceWithGuilds(rows *sqlx.Rows) (*GuildAllianc
 	if err != nil {
 		return nil, err
 	}
+	if parentGuild == nil {
+		return nil, fmt.Errorf("alliance %d references non-existent parent guild %d", alliance.ID, alliance.ParentGuildID)
+	}
 	alliance.ParentGuild = *parentGuild
 	alliance.TotalMembers += parentGuild.MemberCount
 
@@ -105,6 +108,9 @@ func (r *GuildRepository) scanAllianceWithGuilds(rows *sqlx.Rows) (*GuildAllianc
 		if err != nil {
 			return nil, err
 		}
+		if subGuild1 == nil {
+			return nil, fmt.Errorf("alliance %d references non-existent sub guild 1 %d", alliance.ID, alliance.SubGuild1ID)
+		}
 		alliance.SubGuild1 = *subGuild1
 		alliance.TotalMembers += subGuild1.MemberCount
 	}
@@ -114,6 +120,9 @@ func (r *GuildRepository) scanAllianceWithGuilds(rows *sqlx.Rows) (*GuildAllianc
 		if err != nil {
 			return nil, err
 		}
+		if subGuild2 == nil {
+			return nil, fmt.Errorf("alliance %d references non-existent sub guild 2 %d", alliance.ID, alliance.SubGuild2ID)
+		}
 		alliance.SubGuild2 = *subGuild2
 		alliance.TotalMembers += subGuild2.MemberCount
 	}