diff --git a/riven/src/consts/champion.rs b/riven/src/consts/champion.rs
index ca2916a..3d75f1f 100644
--- a/riven/src/consts/champion.rs
+++ b/riven/src/consts/champion.rs
@@ -6,8 +6,6 @@
 //                                           //
 ///////////////////////////////////////////////
 
-use serde::{ Serialize, Deserialize };
-
 newtype_enum! {
     /// A League of Legends champion.
     ///
@@ -174,7 +172,7 @@ newtype_enum! {
     /// `ZILEAN` | "Zilean" | "Zilean" | 26
     /// `ZOE` | "Zoe" | "Zoe" | 142
     /// `ZYRA` | "Zyra" | "Zyra" | 143
-    #[derive(Serialize, Deserialize)]
+    #[derive(serde::Serialize, serde::Deserialize)]
     #[serde(transparent)]
     pub newtype_enum Champion(i16) {
         /// `266`.
@@ -837,6 +835,29 @@ impl Champion {
             _ => None,
         }
     }
+
+    /// https://github.com/MingweiSamuel/Riven/issues/36
+    pub(crate) fn serialize_result<S>(
+        val: &Result<Self, std::num::TryFromIntError>,
+        serializer: S,
+    ) -> Result<S::Ok, S::Error>
+    where
+        S: serde::ser::Serializer,
+    {
+        use serde::ser::Serialize;
+        val.unwrap_or(Champion(-1)).serialize(serializer)
+    }
+
+    /// https://github.com/MingweiSamuel/Riven/issues/36
+    pub(crate) fn deserialize_result<'de, D>(
+        deserializer: D,
+    ) -> Result<Result<Self, std::num::TryFromIntError>, D::Error>
+    where
+        D: serde::de::Deserializer<'de>,
+    {
+        use std::convert::TryInto;
+        <i64 as serde::de::Deserialize>::deserialize(deserializer).map(|id| id.try_into().map(Self))
+    }
 }
 
 impl std::str::FromStr for Champion {
diff --git a/riven/src/models.rs b/riven/src/models.rs
index 7a0eb74..ad0f590 100644
--- a/riven/src/models.rs
+++ b/riven/src/models.rs
@@ -820,7 +820,9 @@ pub mod match_v5 {
         pub champ_level: i32,
         /// Prior to patch 11.4, on Feb 18th, 2021, this field returned invalid championIds. We recommend determining the champion based on the championName field for matches played prior to patch 11.4.
         #[serde(rename = "championId")]
-        pub champion_id: crate::consts::Champion,
+        #[serde(serialize_with = "crate::consts::Champion::serialize_result")]
+        #[serde(deserialize_with = "crate::consts::Champion::deserialize_result")]
+        pub champion_id: Result<crate::consts::Champion, std::num::TryFromIntError>,
         #[serde(rename = "championName")]
         pub champion_name: String,
         /// This field is currently only utilized for Kayn's transformations. (Legal values: 0 - None, 1 - Slayer, 2 - Assassin)
diff --git a/riven/srcgen/consts/champion.rs.dt b/riven/srcgen/consts/champion.rs.dt
index d124218..a650a15 100644
--- a/riven/srcgen/consts/champion.rs.dt
+++ b/riven/srcgen/consts/champion.rs.dt
@@ -16,8 +16,6 @@
     };
 }}{{= dotUtils.preamble() }}
 
-use serde::{ Serialize, Deserialize };
-
 newtype_enum! {
     /// A League of Legends champion.
     ///
@@ -34,7 +32,7 @@ newtype_enum! {
 {{
     }
 }}
-    #[derive(Serialize, Deserialize)]
+    #[derive(serde::Serialize, serde::Deserialize)]
     #[serde(transparent)]
     pub newtype_enum Champion(i16) {
 {{
@@ -92,6 +90,29 @@ impl Champion {
             _ => None,
         }
     }
+
+    /// https://github.com/MingweiSamuel/Riven/issues/36
+    pub(crate) fn serialize_result<S>(
+        val: &Result<Self, std::num::TryFromIntError>,
+        serializer: S,
+    ) -> Result<S::Ok, S::Error>
+    where
+        S: serde::ser::Serializer,
+    {
+        use serde::ser::Serialize;
+        val.unwrap_or(Champion(-1)).serialize(serializer)
+    }
+
+    /// https://github.com/MingweiSamuel/Riven/issues/36
+    pub(crate) fn deserialize_result<'de, D>(
+        deserializer: D,
+    ) -> Result<Result<Self, std::num::TryFromIntError>, D::Error>
+    where
+        D: serde::de::Deserializer<'de>,
+    {
+        use std::convert::TryInto;
+        <i64 as serde::de::Deserialize>::deserialize(deserializer).map(|id| id.try_into().map(Self))
+    }
 }
 
 impl std::str::FromStr for Champion {
diff --git a/riven/srcgen/models.rs.dt b/riven/srcgen/models.rs.dt
index 8c6ca9f..62ba1e9 100644
--- a/riven/srcgen/models.rs.dt
+++ b/riven/srcgen/models.rs.dt
@@ -49,16 +49,22 @@ pub mod {{= dotUtils.changeCase.snakeCase(endpoint) }} {
             for (let [ propKey, prop ] of Object.entries(props))
             {
                 const name = dotUtils.normalizePropName(propKey);
-                const required = requiredSet.has(propKey);
+                const optional = !requiredSet.has(propKey);
 }}
 {{? prop.description }}
         /// {{= prop.description.split('\n').map(x => x.trim()).join('<br>\r\n        /// ') }}
 {{?}}
         {{= dotUtils.formatJsonProperty(propKey) }}
-{{? !required }}
+{{? optional }}
         #[serde(skip_serializing_if = "Option::is_none")]
 {{?}}
-        pub {{= name }}: {{= dotUtils.stringifyType(prop, { optional: !required }) }},
+{{? 'championId' === propKey && (prop.description || '').includes('this field returned invalid championIds') }}
+        #[serde(serialize_with = "crate::consts::Champion::serialize_result")]
+        #[serde(deserialize_with = "crate::consts::Champion::deserialize_result")]
+        pub {{= name }}: Result<crate::consts::Champion, std::num::TryFromIntError>,
+{{??}}
+        pub {{= name }}: {{= dotUtils.stringifyType(prop, { optional }) }},
+{{?}}
 {{
             }
 }}