diff --git a/api/functions/Card/IsCoLinked.yml b/api/functions/Card/IsCoLinked.yml
new file mode 100644
index 0000000..7e96ca8
--- /dev/null
+++ b/api/functions/Card/IsCoLinked.yml
@@ -0,0 +1,22 @@
+---!function
+name: IsCoLinked
+namespace: Card
+description: >-
+  Checks if a card is currently [co-linked](https://yugipedia.com/wiki/Co-linked).
+summary: Checks if a card is currently co-linked.
+parameters:
+  - name: c
+    type: [ Card ]
+    description: The card to check.
+  - name: count
+    type: [ int ]
+    description: The number of co-links to check for.
+    required: false
+    defaultValue: 1
+returns:
+  - type: [ bool ]
+    description: >-
+      `true` if the card is currently co-linked, `false` otherwise.
+status:
+  index: stable
+tags: [ card-check, card-type-related ]
diff --git a/api/functions/Cost/Discard.yml b/api/functions/Cost/Discard.yml
index d4d749d..68ca7eb 100644
--- a/api/functions/Cost/Discard.yml
+++ b/api/functions/Cost/Discard.yml
@@ -14,17 +14,28 @@ parameters:
     type: [ CardFilter ]
     description: Additional filter to be used for the card(s) that are to be discarded (e.g. `Pendulum Monster` for "Dragonpit Magician").
     required: false
-    defaultValue: Card.IsDiscardable
   - name: other
     type: [ bool ]
     description: If set to `true`, the activating card itself will be excluded from the discard check and the discarding itself. Used for effects such as `You can discard 1 other card; ...` as well as Spell/Trap activations (e.g. "Twin Twisters").
     required: false
     defaultValue: false
-  - name: count
-    type: [ int ]
-    description: The number of cards to be discarded.
+  - name: min
+  # TODO: document type of function
+    type: [ int, function ]
+    description: The minimum number of cards to discard.
     required: false
     defaultValue: 1
+  - name: max
+  # TODO: document type of function
+    type: [ int, function ]
+    description: The maximum number of cards to discard.
+    required: false
+    defaultValue: min
+  - name: op
+  # TODO: document type of function
+    type: [ function ]
+    description: Additional handling to apply to the cards after discarding them.
+    required: false
 returns:
   - type: [ EffectCost ]
     description: The cost function generated based on the given parameters.
diff --git a/api/functions/Cost/Reveal.yml b/api/functions/Cost/Reveal.yml
new file mode 100644
index 0000000..22f009c
--- /dev/null
+++ b/api/functions/Cost/Reveal.yml
@@ -0,0 +1,43 @@
+---!function
+name: Reveal
+namespace: Cost
+description: Creates a baseline [cost function](/api/types/EffectCost) used for effects that reveal a card(s) as cost, such as `Reveal 1... in your hand; ...` (e.g. "Amazoness Spy").
+summary: Creates a cost function for effects that reveal a card(s) as cost.
+status:
+  index: stable
+parameters:
+  - name: filter
+    type: [ CardFilter ]
+    description: Additional filter to be used for the card(s) that are to be revealed (e.g. `"Amazoness" monster` for "Amazoness Spy").
+    required: false
+  - name: other
+    type: [ bool ]
+    description: If set to `true`, the activating card itself will be excluded from the reveal check and the revealing itself. Used for effects such as `You can reveal 1 other... in your hand; ...` (e.g. "Amazoness Spy").
+    required: false
+    defaultValue: false
+  - name: min
+  # TODO: document type of function
+    type: [ int, function ]
+    description: The minimum number of cards to reveal.
+    required: false
+    defaultValue: 1
+  - name: max
+  # TODO: document type of function
+    type: [ int, function ]
+    description: The maximum number of cards to reveal.
+    required: false
+    defaultValue: min
+  - name: op
+  # TODO: document type of function
+    type: [ function ]
+    description: Additional handling to apply to the cards after revealing them.
+    required: false
+  - name: location
+    type: [ int ]
+    description: The location to reveal cards from.
+    required: false
+    defaultValue: LOCATION_HAND
+returns:
+  - type: [ EffectCost ]
+    description: The cost function generated based on the given parameters.
+    guaranteed: true