diff --git a/client/src/components/inventory.tsx b/client/src/components/inventory.tsx
index b26ecf1..0adf55d 100644
--- a/client/src/components/inventory.tsx
+++ b/client/src/components/inventory.tsx
@@ -12,6 +12,7 @@ import { store } from '../state/store';
 import { useSelector } from 'react-redux';
 import { useTranslation } from 'react-i18next';
 import { t } from 'i18next';
+import { WorldLevelIdContext } from './infoview/context';
 
 export function Inventory({levelInfo, openDoc, lemmaTab, setLemmaTab, enableAll=false} :
   {
@@ -57,6 +58,7 @@ function InventoryList({items, docType, openDoc, tab=null, setTab=undefined, lev
   // been loaded. Is there a better way to observe this?
 
   const gameId = React.useContext(GameIdContext)
+  const {worldId, levelId} = React.useContext(WorldLevelIdContext)
 
   const difficulty = useSelector(selectDifficulty(gameId))
 
@@ -73,12 +75,15 @@ function InventoryList({items, docType, openDoc, tab=null, setTab=undefined, lev
   let inv: string[] = selectInventory(gameId)(store.getState())
   let modifiedItems : InventoryTile[] = items.map(tile => inv.includes(tile.name) ? {...tile, locked: false} : tile)
 
+  // Item(s) proved in the preceeding level
+  let recentItems = modifiedItems.filter(x => x.world == worldId && x.level == levelId - 1)
+
   return <>
     {categories.length > 1 &&
       <div className="tab-bar">
         {categories.map((cat) => {
           let hasNew = modifiedItems.filter(item => item.new && (cat == item.category)).length > 0
-          return <div key={`category-${cat}`} className={`tab${cat == (tab ?? categories[0]) ? " active": ""}${hasNew ? " new": ""}`}
+          return <div key={`category-${cat}`} className={`tab${cat == (tab ?? categories[0]) ? " active": ""}${hasNew ? ' new': ''}${recentItems.map(x => x.category).includes(cat) ? ' recent': ''}`}
             onClick={() => { setTab(cat) }}>{cat}</div>})}
       </div>}
     <div className="inventory-list">
@@ -91,14 +96,16 @@ function InventoryList({items, docType, openDoc, tab=null, setTab=undefined, lev
               item={item}
               showDoc={() => {openDoc({name: item.name, type: docType})}}
               name={item.name} displayName={item.displayName} locked={difficulty > 0 ? item.locked : false}
-              disabled={item.disabled} newly={item.new} enableAll={enableAll} />
+              disabled={item.disabled}
+              recent={recentItems.map(x => x.name).includes(item.name)}
+              newly={item.new} enableAll={enableAll} />
         })
       }
     </div>
     </>
 }
 
-function InventoryItem({item, name, displayName, locked, disabled, newly, showDoc, enableAll=false}) {
+function InventoryItem({item, name, displayName, locked, disabled, newly, showDoc, recent=false, enableAll=false}) {
   const icon = locked ? <FontAwesomeIcon icon={faLock} /> :
                disabled ? <FontAwesomeIcon icon={faBan} /> : item.st
   const className = locked ? "locked" : disabled ? "disabled" : newly ? "new" : ""
@@ -124,7 +131,7 @@ function InventoryItem({item, name, displayName, locked, disabled, newly, showDo
     ev.stopPropagation()
   }
 
-return <div className={`item ${className}${enableAll ? ' enabled' : ''}`} onClick={handleClick} title={title}>
+return <div className={`item ${className}${enableAll ? ' enabled' : ''}${recent ? ' recent' : ''}`} onClick={handleClick} title={title}>
     {icon} {displayName}
     <div className="copy-button" onClick={copyItemName}>
       {copied ? <FontAwesomeIcon icon={faCheck} /> : <FontAwesomeIcon icon={faClipboard} />}
diff --git a/client/src/css/inventory.css b/client/src/css/inventory.css
index d3fc5b6..f18292c 100644
--- a/client/src/css/inventory.css
+++ b/client/src/css/inventory.css
@@ -46,6 +46,9 @@
   background-color: rgb(255, 242, 190);
 }
 
+.inventory .item.recent {
+  background-color: rgb(242, 190, 255);
+}
 .inventory .item:not(.locked), .inventory .item.enabled {
   cursor: pointer;
 }
@@ -72,6 +75,14 @@
   border-bottom: 0.3em solid var(--clr-primary);
 }
 
+.inventory .tab.recent {
+  background-image: linear-gradient(to bottom, rgba(255,0,0,0), rgb(242, 190, 255));
+}
+
+.inventory .tab.recent:not(.active) {
+  border-bottom: 0.3em solid rgb(242, 190, 255);
+}
+
 .inventory .tab.new {
   background-image: linear-gradient(to bottom, rgba(255,0,0,0), rgb(255, 242, 190));
 }
diff --git a/client/src/state/api.ts b/client/src/state/api.ts
index 1a64597..8a88119 100644
--- a/client/src/state/api.ts
+++ b/client/src/state/api.ts
@@ -36,6 +36,9 @@ export interface InventoryTile {
   new: boolean,
   hidden: boolean
   altTitle: string,
+  world : string|null,
+  level : number|null,
+  proven : boolean
 }
 
 export interface LevelInfo {
diff --git a/server/GameServer/Commands.lean b/server/GameServer/Commands.lean
index 76544f9..c2ba0a0 100644
--- a/server/GameServer/Commands.lean
+++ b/server/GameServer/Commands.lean
@@ -973,6 +973,10 @@ elab "MakeGame" : command => do
               name := name
               displayName := data.displayName
               category := data.category
+              world := worldId
+              -- from the previous level. This is fine b/c in practise levels start at 1
+              level := (levelId - 1 : Nat)
+              proven := true
               altTitle := data.statement
               locked := false }
 
diff --git a/server/GameServer/EnvExtensions.lean b/server/GameServer/EnvExtensions.lean
index d2a47d5..d2b86c4 100644
--- a/server/GameServer/EnvExtensions.lean
+++ b/server/GameServer/EnvExtensions.lean
@@ -93,6 +93,12 @@ structure InventoryTile where
   displayName : String
   /-- Category to group inventory items by (currently only used for lemmas). -/
   category : String
+  /-- The world which introduced this item. -/
+  world : Option Name := none
+  /-- The level which introduced this item. -/
+  level : Option Nat := none
+  /-- Set to `true` if there exists an exercise in the game proving this statement. -/
+  proven := false
   /-- If `true` then the item only gets unlocked in a later level. -/
   locked := true
   /-- If `true` then the item is blocked for this level. -/