diff --git a/api/functions/Auxiliary/SelfDiscardCost.yml b/api/functions/Auxiliary/SelfDiscardCost.yml
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+++ b/api/functions/Auxiliary/SelfDiscardCost.yml
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+---!function
+name: SelfDiscardCost
+namespace: aux
+description: A baseline [cost function](/api/types/EffectCost) used for effects that discard the activating card itself as cost, such as `You can discard this card; ...` (e.g. "Ash Blossom & Joyous Spring").
+summary: Cost function for effects that discard the card itself as cost.
+status:
+  index: stable
+parameters:
+  - name: e
+    type: [ Effect ]
+    description: The effect being activated.
+  - name: tp
+    type: [ int ]
+    description: The player activating the effect.
+  - name: eg
+    type: [ Group ]
+    description: A group of cards associated to the event that prompted the effect activation. The specifics of this group vary depending on the [event code](/api/enums/Event).
+  - name: ep
+    type: [ int ]
+    description: The player associated to the event that prompted the effect activation.
+  - name: ev
+    type: [ Group ]
+    description: A value associated to the event that prompted the effect activation. The specifics of this value vary depending on the event code.
+  - name: re
+    type: [ Effect ]
+    description: The effect that caused the event that prompted the effect activation.
+  - name: r
+    type: [ int ]
+    description: Composite [Reason](/api/enums/Reason) value of the event that prompted the effect activation.
+  - name: rp
+    type: [ int ]
+    description: The player that caused the event that prompted the effect activation.
+  - name: chk
+    type: [ int ]
+    description: Must be `0` when checking if the cost can be paid, and `1` when performing the cost.
+returns:
+  - type: [ bool ]
+    description: If `chk` is `0`, returns `true` if the cost can be paid.
+    guaranteed: false
diff --git a/api/functions/Auxiliary/SelfDiscardToGraveCost.yml b/api/functions/Auxiliary/SelfDiscardToGraveCost.yml
new file mode 100644
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+++ b/api/functions/Auxiliary/SelfDiscardToGraveCost.yml
@@ -0,0 +1,39 @@
+---!function
+name: SelfDiscardToGraveCost
+namespace: aux
+description: A baseline [cost function](/api/types/EffectCost) used for effects that discard the activating card itself to the GY as cost, such as `You can discard this card to the GY; ...` (e.g. "D.D. Crow").
+summary: Cost function for effects that discard the card itself to the GY as cost.
+status:
+  index: stable
+parameters:
+  - name: e
+    type: [ Effect ]
+    description: The effect being activated.
+  - name: tp
+    type: [ int ]
+    description: The player activating the effect.
+  - name: eg
+    type: [ Group ]
+    description: A group of cards associated to the event that prompted the effect activation. The specifics of this group vary depending on the [event code](/api/enums/Event).
+  - name: ep
+    type: [ int ]
+    description: The player associated to the event that prompted the effect activation.
+  - name: ev
+    type: [ Group ]
+    description: A value associated to the event that prompted the effect activation. The specifics of this value vary depending on the event code.
+  - name: re
+    type: [ Effect ]
+    description: The effect that caused the event that prompted the effect activation.
+  - name: r
+    type: [ int ]
+    description: Composite [Reason](/api/enums/Reason) value of the event that prompted the effect activation.
+  - name: rp
+    type: [ int ]
+    description: The player that caused the event that prompted the effect activation.
+  - name: chk
+    type: [ int ]
+    description: Must be `0` when checking if the cost can be paid, and `1` when performing the cost.
+returns:
+  - type: [ bool ]
+    description: If `chk` is `0`, returns `true` if the cost can be paid.
+    guaranteed: false
diff --git a/api/functions/Auxiliary/SelfToDeckCost.yml b/api/functions/Auxiliary/SelfToDeckCost.yml
new file mode 100644
index 0000000..d987a8f
--- /dev/null
+++ b/api/functions/Auxiliary/SelfToDeckCost.yml
@@ -0,0 +1,39 @@
+---!function
+name: SelfToDeckCost
+namespace: aux
+description: A baseline [cost function](/api/types/EffectCost) used for effects that shuffle the activating card itself to the Main Deck as cost, such as `You can shuffle this card (you control/from.../etc) into the Deck; ...` (e.g. the "Rescue Ferret").
+summary: Cost function for effects that shuffle the card itself to the Deck as cost.
+status:
+  index: stable
+parameters:
+  - name: e
+    type: [ Effect ]
+    description: The effect being activated.
+  - name: tp
+    type: [ int ]
+    description: The player activating the effect.
+  - name: eg
+    type: [ Group ]
+    description: A group of cards associated to the event that prompted the effect activation. The specifics of this group vary depending on the [event code](/api/enums/Event).
+  - name: ep
+    type: [ int ]
+    description: The player associated to the event that prompted the effect activation.
+  - name: ev
+    type: [ Group ]
+    description: A value associated to the event that prompted the effect activation. The specifics of this value vary depending on the event code.
+  - name: re
+    type: [ Effect ]
+    description: The effect that caused the event that prompted the effect activation.
+  - name: r
+    type: [ int ]
+    description: Composite [Reason](/api/enums/Reason) value of the event that prompted the effect activation.
+  - name: rp
+    type: [ int ]
+    description: The player that caused the event that prompted the effect activation.
+  - name: chk
+    type: [ int ]
+    description: Must be `0` when checking if the cost can be paid, and `1` when performing the cost.
+returns:
+  - type: [ bool ]
+    description: If `chk` is `0`, returns `true` if the cost can be paid.
+    guaranteed: false
diff --git a/api/functions/Auxiliary/SelfToExtraCost.yml b/api/functions/Auxiliary/SelfToExtraCost.yml
new file mode 100644
index 0000000..a3c56cd
--- /dev/null
+++ b/api/functions/Auxiliary/SelfToExtraCost.yml
@@ -0,0 +1,39 @@
+---!function
+name: SelfToExtraCost
+namespace: aux
+description: A baseline [cost function](/api/types/EffectCost) used for effects that return the activating card itself to the Extra Deck as cost, such as `You can return this card (you control/from.../etc) to the Extra Deck; ...` (e.g. the "Gladiator Beast Gyzarus").
+summary: Cost function for effects that return the card itself to the Extra Deck as cost.
+status:
+  index: stable
+parameters:
+  - name: e
+    type: [ Effect ]
+    description: The effect being activated.
+  - name: tp
+    type: [ int ]
+    description: The player activating the effect.
+  - name: eg
+    type: [ Group ]
+    description: A group of cards associated to the event that prompted the effect activation. The specifics of this group vary depending on the [event code](/api/enums/Event).
+  - name: ep
+    type: [ int ]
+    description: The player associated to the event that prompted the effect activation.
+  - name: ev
+    type: [ Group ]
+    description: A value associated to the event that prompted the effect activation. The specifics of this value vary depending on the event code.
+  - name: re
+    type: [ Effect ]
+    description: The effect that caused the event that prompted the effect activation.
+  - name: r
+    type: [ int ]
+    description: Composite [Reason](/api/enums/Reason) value of the event that prompted the effect activation.
+  - name: rp
+    type: [ int ]
+    description: The player that caused the event that prompted the effect activation.
+  - name: chk
+    type: [ int ]
+    description: Must be `0` when checking if the cost can be paid, and `1` when performing the cost.
+returns:
+  - type: [ bool ]
+    description: If `chk` is `0`, returns `true` if the cost can be paid.
+    guaranteed: false
diff --git a/api/functions/Auxiliary/SelfToHandCost.yml b/api/functions/Auxiliary/SelfToHandCost.yml
new file mode 100644
index 0000000..b39a3c3
--- /dev/null
+++ b/api/functions/Auxiliary/SelfToHandCost.yml
@@ -0,0 +1,39 @@
+---!function
+name: SelfToHandCost
+namespace: aux
+description: A baseline [cost function](/api/types/EffectCost) used for effects that return the activating card itself to the hand as cost, such as `You can return this card (you control/from.../etc) to the/your hand; ...` (e.g. "Sauravis, the Ancient and Ascended").
+summary: Cost function for effects that return the card itself to the hand as cost.
+status:
+  index: stable
+parameters:
+  - name: e
+    type: [ Effect ]
+    description: The effect being activated.
+  - name: tp
+    type: [ int ]
+    description: The player activating the effect.
+  - name: eg
+    type: [ Group ]
+    description: A group of cards associated to the event that prompted the effect activation. The specifics of this group vary depending on the [event code](/api/enums/Event).
+  - name: ep
+    type: [ int ]
+    description: The player associated to the event that prompted the effect activation.
+  - name: ev
+    type: [ Group ]
+    description: A value associated to the event that prompted the effect activation. The specifics of this value vary depending on the event code.
+  - name: re
+    type: [ Effect ]
+    description: The effect that caused the event that prompted the effect activation.
+  - name: r
+    type: [ int ]
+    description: Composite [Reason](/api/enums/Reason) value of the event that prompted the effect activation.
+  - name: rp
+    type: [ int ]
+    description: The player that caused the event that prompted the effect activation.
+  - name: chk
+    type: [ int ]
+    description: Must be `0` when checking if the cost can be paid, and `1` when performing the cost.
+returns:
+  - type: [ bool ]
+    description: If `chk` is `0`, returns `true` if the cost can be paid.
+    guaranteed: false