diff --git a/CLAUDE.md b/CLAUDE.md
index c46e22e..b205c3d 100644
--- a/CLAUDE.md
+++ b/CLAUDE.md
@@ -86,6 +86,12 @@ Three-layer split; `JCA` is the single global namespace:
     `config.discovered` (saved immediately via `SMODS.save_mod_config`) and
     per-run in `G.GAME.jca_run_combos`. Undiscovered pairs render face-down
     with a `???` caption in the Combos tab; blurb replaces it once fielded.
+    Themes (every `theme_info` tag) persist in `config.themes_found` once
+    two DIFFERENT jokers connect the tag (giver + wanter; a joker carrying
+    both sides needs a second joker). One toast per emplacement, famous
+    pair outranking theme. Badge/progress render in `theme_tab_def`; toast
+    names come from `JCA.theme_names` (filled after THEME_TABS, used only
+    at gameplay time).
   - Post-run recap: wraps `create_UIBox_game_over`/`create_UIBox_win` and
     inserts a "Combos fielded this run" row (from `G.GAME.jca_run_combos`)
     relative to vanilla button ids (`from_game_over`; `from_game_won` or
diff --git a/README.md b/README.md
index 19788fa..568b004 100644
--- a/README.md
+++ b/README.md
@@ -16,6 +16,10 @@ recommends joker combos while you play:
   "New combo!" toast fires and the pair is permanently inked into the
   catalog — until then its cards sit face-down with a "???" caption, so
   filling in the Combos tab becomes its own collection hunt.
+- **Theme discovery**: assembling any synergy theme for the first time —
+  one joker that provides it plus another that wants it — fires a
+  "Theme explored!" toast, badges that theme's catalog page, and counts
+  toward a per-tab progress line ("3 of 10 themes explored").
 - **Hover a joker you own** to see its active combos with the rest of your
   lineup.
 - **Browse the synergy catalog** any time: a purple **Combos** button in the
diff --git a/config.lua b/config.lua
index cd0c827..1bfe3bf 100644
--- a/config.lua
+++ b/config.lua
@@ -6,4 +6,5 @@ return {
     threshold = 4,         -- total synergy score needed to recommend a card
     learning_mode = false, -- hide verdicts (pulse, "Strong pick!"), keep reasons
     discovered = {},       -- famous pairs the player has fielded (pair keys)
+    themes_found = {},     -- synergy themes the player has assembled (tags)
 }
diff --git a/main.lua b/main.lua
index 891aba4..45ed776 100644
--- a/main.lua
+++ b/main.lua
@@ -18,8 +18,10 @@ JCA.db = data.jokers
 -- Fallback defaults keep the engine usable outside the game (tests).
 JCA.mod = SMODS.current_mod
 JCA.config = SMODS.current_mod and SMODS.current_mod.config
-    or { pulse = true, owned_tooltip = true, threshold = 4, discovered = {} }
+    or { pulse = true, owned_tooltip = true, threshold = 4,
+         discovered = {}, themes_found = {} }
 JCA.config.discovered = JCA.config.discovered or {}
+JCA.config.themes_found = JCA.config.themes_found or {}
 
 -- Explicit famous pairs, stored under a canonical "a|b" key (a < b).
 JCA.pair_list = data.pairs
@@ -315,8 +317,43 @@ function JCA.check_discoveries()
             end
         end
     end
+    -- Theme discovery: a theme is explored once two DIFFERENT fielded jokers
+    -- connect it — one gives the tag, another wants it (cluster members do
+    -- both, so any two of them qualify).
+    local new_theme
+    for tag in pairs(data.theme_info or {}) do
+        if not JCA.config.themes_found[tag] then
+            local giver, wanter
+            for idx, k in ipairs(keys) do
+                local e = JCA.db[k]
+                if e then
+                    if e.gives[tag] and not giver then giver = idx end
+                    if e.wants[tag] and not wanter then wanter = idx end
+                end
+            end
+            if giver and wanter and giver == wanter then
+                wanter = nil -- same joker on both sides: find a second one
+                for idx, k in ipairs(keys) do
+                    local e = JCA.db[k]
+                    if e and idx ~= giver and (e.gives[tag] or e.wants[tag]) then
+                        wanter = idx
+                        break
+                    end
+                end
+            end
+            if giver and wanter then
+                JCA.config.themes_found[tag] = true
+                new_theme = new_theme or tag
+            end
+        end
+    end
+
+    if (new_pair or new_theme) and JCA.mod and SMODS.save_mod_config then
+        SMODS.save_mod_config(JCA.mod)
+    end
+    -- One toast per emplacement; a famous pair outranks a theme (both stay
+    -- recorded either way).
     if new_pair then
-        if JCA.mod and SMODS.save_mod_config then SMODS.save_mod_config(JCA.mod) end
         pcall(function()
             attention_text({
                 text = 'New combo: ' .. new_pair .. '!',
@@ -326,6 +363,18 @@ function JCA.check_discoveries()
             })
             play_sound('card1', 1.1, 0.6)
         end)
+    elseif new_theme then
+        pcall(function()
+            attention_text({
+                text = 'Theme explored: '
+                    .. ((JCA.theme_names and JCA.theme_names[new_theme]) or new_theme)
+                    .. '!',
+                scale = 0.7, hold = 4, major = G.play, align = 'cm',
+                offset = {x = 0, y = -3.5}, silent = true,
+                backdrop_colour = G.C.SECONDARY_SET.Planet,
+            })
+            play_sound('card1', 1.1, 0.6)
+        end)
     end
 end
 
@@ -463,6 +512,13 @@ local THEME_TABS = {
     }},
 }
 
+-- Display names for theme tags (used by the discovery toast, which runs
+-- before this point in the file but only ever fires during gameplay).
+JCA.theme_names = {}
+for _, group in ipairs(THEME_TABS) do
+    for _, t in ipairs(group.themes) do JCA.theme_names[t.tag] = t.name end
+end
+
 -- Joker keys for a tag, split into pure sources (give only), pure payoffs
 -- (want only), and cluster members (both). Sorted by display name.
 local function theme_members(tag)
@@ -625,10 +681,18 @@ local function theme_tab_def(group, page_no)
     if #both > 0 then groups[#groups + 1] = both end
     if #sources > 0 then groups[#groups + 1] = sources; captions = captions + 1 end
     if #payoffs > 0 then groups[#groups + 1] = payoffs; captions = captions + 1 end
-    local layout = pick_layout(groups, 1 + #blurb_lines + captions)
+    -- +2 text rows: the title and the group progress line above the pager
+    local layout = pick_layout(groups, 2 + #blurb_lines + captions)
 
     local nodes = {}
-    add_caption(nodes, theme.name)
+    if JCA.config.themes_found[theme.tag] then
+        nodes[#nodes + 1] = {n = G.UIT.R, config = {align = 'cm', padding = 0.02}, nodes = {
+            {n = G.UIT.T, config = {text = theme.name, colour = G.C.GOLD, scale = 0.3}},
+            {n = G.UIT.T, config = {text = '  explored!', colour = G.C.GREEN, scale = 0.3}},
+        }}
+    else
+        add_caption(nodes, theme.name)
+    end
     add_info_rows(nodes, data.theme_info[theme.tag], 70, 0.26)
     if #both > 0 then
         add_card_rows(nodes, both, layout.scale, layout.per_row)
@@ -641,6 +705,16 @@ local function theme_tab_def(group, page_no)
         add_caption(nodes, 'Payoffs - these want it')
         add_card_rows(nodes, payoffs, layout.scale, layout.per_row)
     end
+    local explored = 0
+    for _, t in ipairs(group.themes) do
+        if JCA.config.themes_found[t.tag] then explored = explored + 1 end
+    end
+    nodes[#nodes + 1] = {n = G.UIT.R, config = {align = 'cm', padding = 0.02}, nodes = {
+        {n = G.UIT.T, config = {
+            text = ('%d of %d themes explored - field a source and a payoff together')
+                :format(explored, #group.themes),
+            colour = G.C.UI.TEXT_LIGHT, scale = 0.24}},
+    }}
     local options = {}
     for i, t in ipairs(group.themes) do options[i] = t.name end
     nodes[#nodes + 1] = pager_row(options, page_no, 'jca_page_' .. group.label)