diff --git a/transformers/GridCharacterTransformer.tsx b/transformers/GridCharacterTransformer.tsx
new file mode 100644
index 00000000..1272a3d4
--- /dev/null
+++ b/transformers/GridCharacterTransformer.tsx
@@ -0,0 +1,39 @@
+import * as Character from './CharacterTransformer'
+
+// Transforms API response to GridCharacter object
+export function toObject(data: any): GridCharacter {
+  return {
+    id: data.id,
+    object: Character.toObject(data.object),
+    position: data.position,
+    uncapLevel: data.uncap_level,
+    transcendenceStep: data.transcendence_step,
+    mastery: {
+      overMastery: data.over_mastery,
+      aetherialMastery: data.aetherial_mastery,
+      awakening: {
+        type: Awakening.toObject(data.awakening.type),
+        level: data.awakening.awakening_level,
+      },
+      perpetuity: data.perpetuity,
+    },
+  }
+}
+
+// Transforms User object into API parameters
+export function toParams(data: GridCharacter): GridCharacterParams {
+  return {
+    character_id: data.id,
+    position: data.position,
+    uncap_level: data.uncapLevel,
+    transcendence_step: data.transcendenceStep,
+    ring1: data.mastery.overMastery[1],
+    ring2: data.mastery.overMastery[2],
+    ring3: data.mastery.overMastery[3],
+    ring4: data.mastery.overMastery[4],
+    earring: data.mastery.aetherialMastery,
+    awakening_id: data.mastery.awakening.type.id,
+    awakening_level: data.mastery.awakening.level,
+    perpetuity: data.mastery.perpetuity,
+  }
+}
diff --git a/types/GridCharacter.d.ts b/types/GridCharacter.d.ts
index 16089096..b0549ab0 100644
--- a/types/GridCharacter.d.ts
+++ b/types/GridCharacter.d.ts
@@ -2,13 +2,15 @@ interface GridCharacter {
   id: string
   position: number
   object: Character
-  uncap_level: number
-  transcendence_step: number
-  over_mastery: CharacterOverMastery
-  aetherial_mastery: ExtendedMastery
-  awakening: {
-    type: Awakening
-    level: number
+  uncapLevel: number
+  transcendenceStep: number
+  mastery: {
+    overMastery: CharacterOverMastery
+    aetherialMastery: ExtendedMastery
+    awakening: {
+      type: Awakening
+      level: number
+    }
+    perpetuity: boolean
   }
-  perpetuity: boolean
 }
diff --git a/types/GridCharacterParams.d.ts b/types/GridCharacterParams.d.ts
new file mode 100644
index 00000000..205d1ab0
--- /dev/null
+++ b/types/GridCharacterParams.d.ts
@@ -0,0 +1,14 @@
+interface GridCharacterParams {
+  character_id: string
+  position?: number
+  uncap_level?: number
+  transcendence_step?: number
+  ring1?: ExtendedMastery
+  ring2?: ExtendedMastery
+  ring3?: ExtendedMastery
+  ring4?: ExtendedMastery
+  earring: ExtendedMastery
+  awakening_id?: string
+  awakening_level?: number
+  perpetuity?: boolean
+}