diff --git a/src/networks/butterflynet/mod.rs b/src/networks/butterflynet/mod.rs
index fe3ac2f6cf25..59ddd242b572 100644
--- a/src/networks/butterflynet/mod.rs
+++ b/src/networks/butterflynet/mod.rs
@@ -106,6 +106,7 @@ pub static HEIGHT_INFOS: LazyLock<HashMap<Height, HeightInfo>> = LazyLock::new(|
         make_height!(Teep, 50, get_bundle_cid("v16.0.1")),
         make_height!(Tock, 100),
         make_height!(GoldenWeek, 200, get_bundle_cid("v17.0.0")),
+        make_height!(Xxx, i64::MAX),
     ])
 });
 
diff --git a/src/networks/calibnet/mod.rs b/src/networks/calibnet/mod.rs
index 139220ad885f..7390553b315a 100644
--- a/src/networks/calibnet/mod.rs
+++ b/src/networks/calibnet/mod.rs
@@ -95,6 +95,7 @@ pub static HEIGHT_INFOS: LazyLock<HashMap<Height, HeightInfo>> = LazyLock::new(|
         make_height!(TockFix, 2_558_014, get_bundle_cid("v16.0.1")),
         // Wed 10 Sep 23:00:00 UTC 2025
         make_height!(GoldenWeek, 3_007_294, get_bundle_cid("v17.0.0")),
+        make_height!(Xxx, i64::MAX),
     ])
 });
 
diff --git a/src/networks/devnet/mod.rs b/src/networks/devnet/mod.rs
index 5c968b6e7567..2926f204df04 100644
--- a/src/networks/devnet/mod.rs
+++ b/src/networks/devnet/mod.rs
@@ -164,6 +164,10 @@ pub static HEIGHT_INFOS: LazyLock<HashMap<Height, HeightInfo>> = LazyLock::new(|
             get_upgrade_height_from_env("FOREST_GOLDEN_WEEK_HEIGHT").unwrap_or(9999999999),
             get_bundle_cid("v17.0.0")
         ),
+        make_height!(
+            Xxx,
+            get_upgrade_height_from_env("FOREST_XXX_HEIGHT").unwrap_or(9999999999)
+        ),
     ])
 });
 
diff --git a/src/networks/mainnet/mod.rs b/src/networks/mainnet/mod.rs
index f9443aa399c3..6440bdfaec53 100644
--- a/src/networks/mainnet/mod.rs
+++ b/src/networks/mainnet/mod.rs
@@ -92,6 +92,7 @@ pub static HEIGHT_INFOS: LazyLock<HashMap<Height, HeightInfo>> = LazyLock::new(|
         make_height!(Tock, 4_878_840 + EPOCHS_IN_DAY * 90),
         // Wed 24 Sep 23:00:00 UTC 2025
         make_height!(GoldenWeek, 5_348_280, get_bundle_cid("v17.0.0")),
+        make_height!(Xxx, i64::MAX),
     ])
 });
 
diff --git a/src/networks/mod.rs b/src/networks/mod.rs
index c4cf7ec55593..fa260145762c 100644
--- a/src/networks/mod.rs
+++ b/src/networks/mod.rs
@@ -48,7 +48,7 @@ pub mod mainnet;
 pub mod metrics;
 
 /// Newest network version for all networks
-pub const NEWEST_NETWORK_VERSION: NetworkVersion = NetworkVersion::V25;
+pub const NEWEST_NETWORK_VERSION: NetworkVersion = NetworkVersion::V27;
 
 const ENV_FOREST_BLOCK_DELAY_SECS: &str = "FOREST_BLOCK_DELAY_SECS";
 const ENV_FOREST_PROPAGATION_DELAY_SECS: &str = "FOREST_PROPAGATION_DELAY_SECS";
@@ -176,6 +176,7 @@ pub enum Height {
     Tock,
     TockFix,
     GoldenWeek,
+    Xxx,
 }
 
 impl From<Height> for NetworkVersion {
@@ -216,6 +217,7 @@ impl From<Height> for NetworkVersion {
             Height::Tock => NetworkVersion::V26,
             Height::TockFix => NetworkVersion::V26,
             Height::GoldenWeek => NetworkVersion::V27,
+            Height::Xxx => NetworkVersion::V28,
         }
     }
 }
@@ -639,7 +641,7 @@ mod tests {
     fn heights_are_present(height_infos: &HashMap<Height, HeightInfo>) {
         /// These are required heights that need to be defined for all networks, for, e.g., conformance
         /// with `Filecoin.StateGetNetworkParams` RPC method.
-        const REQUIRED_HEIGHTS: [Height; 30] = [
+        const REQUIRED_HEIGHTS: [Height; 31] = [
             Height::Breeze,
             Height::Smoke,
             Height::Ignition,
@@ -670,6 +672,7 @@ mod tests {
             Height::TukTuk,
             Height::Teep,
             Height::GoldenWeek,
+            Height::Xxx,
         ];
 
         for height in &REQUIRED_HEIGHTS {
diff --git a/src/rpc/methods/state.rs b/src/rpc/methods/state.rs
index f2e3d35ac9ae..fe3d66a18707 100644
--- a/src/rpc/methods/state.rs
+++ b/src/rpc/methods/state.rs
@@ -3143,6 +3143,7 @@ pub struct ForkUpgradeParams {
     upgrade_teep_height: ChainEpoch,
     upgrade_tock_height: ChainEpoch,
     //upgrade_golden_week_height: ChainEpoch,
+    //upgrade_xxx_height: ChainEpoch,
 }
 
 impl TryFrom<&ChainConfig> for ForkUpgradeParams {
@@ -3191,6 +3192,7 @@ impl TryFrom<&ChainConfig> for ForkUpgradeParams {
             upgrade_teep_height: get_height(Teep)?,
             upgrade_tock_height: get_height(Tock)?,
             //upgrade_golden_week_height: get_height(GoldenWeek)?,
+            //upgrade_xxx_height: get_height(Xxx)?,
         })
     }
 }
diff --git a/src/utils/misc/logo.rs b/src/utils/misc/logo.rs
index 10a5c6cf56d8..c6f94708803b 100644
--- a/src/utils/misc/logo.rs
+++ b/src/utils/misc/logo.rs
@@ -32,6 +32,7 @@ pub fn reveal_upgrade_logo(network_version: NetworkVersion) {
         NetworkVersion::V24 => reveal_tuktuk_upgrade(),
         NetworkVersion::V25 => reveal_teep_upgrade(),
         NetworkVersion::V27 => reveal_golden_week_upgrade(),
+        NetworkVersion::V28 => reveal_xxx_upgrade(),
         _ => reveal_three_trees(),
     }
 }
@@ -239,3 +240,12 @@ fn reveal_golden_week_upgrade() {
         "###
     );
 }
+
+/// Reveals the `Xxx` upgrade logo.
+fn reveal_xxx_upgrade() {
+    info!(
+        r###"
+    Xxx!
+        "###
+    );
+}