diff --git a/src/data/layers/coal.tsx b/src/data/layers/coal.tsx
index b8ac8ed..b09edb4 100644
--- a/src/data/layers/coal.tsx
+++ b/src/data/layers/coal.tsx
@@ -169,7 +169,10 @@ const layer = createLayer(id, function (this: BaseLayer) {
             return Decimal.pow(0.95, paper.books.bonfireBook.totalAmount.value).times(10);
         },
         inverseCost(x: DecimalSource) {
-            return Decimal.div(x, Decimal.pow(0.95, paper.books.bonfireBook.totalAmount.value).times(10)).floor();
+            return Decimal.div(
+                x,
+                Decimal.pow(0.95, paper.books.bonfireBook.totalAmount.value).times(10)
+            ).floor();
         },
         display: jsx(() => (
             <>
@@ -301,10 +304,10 @@ const layer = createLayer(id, function (this: BaseLayer) {
         },
         inverseCost(x: DecimalSource) {
             if (management.elfTraining.coalDrillElfTraining.milestones[2].earned.value) {
-                x = Decimal.div(x, 10);
+                x = Decimal.mul(x, 10);
             }
             if (management.elfTraining.fertilizerElfTraining.milestones[2].earned.value) {
-                x = Decimal.div(x, Decimal.add(trees.totalLogs.value, Math.E).ln());
+                x = Decimal.mul(x, Decimal.add(trees.totalLogs.value, Math.E).ln());
             }
             let v = Decimal.div(x, 10).log(1.15);
             v = v.div(Decimal.pow(0.95, paper.books.coalDrillBook.totalAmount.value));
diff --git a/src/data/layers/elves.tsx b/src/data/layers/elves.tsx
index 0770aec..5bad141 100644
--- a/src/data/layers/elves.tsx
+++ b/src/data/layers/elves.tsx
@@ -11,7 +11,7 @@ import { main } from "data/projEntry";
 import { createBar, GenericBar } from "features/bars/bar";
 import { GenericBuyable } from "features/buyable";
 import { ClickableOptions } from "features/clickables/clickable";
-import { jsx, showIf } from "features/feature";
+import { jsx, showIf, Visibility } from "features/feature";
 import { createMilestone } from "features/milestones/milestone";
 import { createReset } from "features/reset";
 import { Resource } from "features/resources/resource";
@@ -110,6 +110,9 @@ const layer = createLayer(id, function (this: BaseLayer) {
                     coal.betterFertilizer.bought.value = true;
                     coal.unlockKiln.bought.value = true;
                     coal.efficientSmelther.bought.value = true;
+                    coal.arsonistAssistance.bought.value = true;
+                    coal.refinedCoal.bought.value = true;
+                    coal.coloredFire.bought.value = true;
                 }
             });
         }
@@ -585,6 +588,9 @@ const layer = createLayer(id, function (this: BaseLayer) {
 
                 (isArray(options.buyable) ? options.buyable : [options.buyable]).forEach(
                     buyable => {
+                        if (unref(buyable.visibility) !== Visibility.Visible) {
+                            return;
+                        }
                         const buyAmount = Decimal.min(
                             Decimal.sub(
                                 buyable.inverseCost(buyable.resource?.value),
diff --git a/src/data/layers/oil.tsx b/src/data/layers/oil.tsx
index 89df301..2303e15 100644
--- a/src/data/layers/oil.tsx
+++ b/src/data/layers/oil.tsx
@@ -101,14 +101,14 @@ const layer = createLayer(id, function (this: BaseLayer) {
         resource: metal.metal,
         cost() {
             let v = new Decimal(this.amount.value);
-            if (Decimal.gte(v, 100)) v = Decimal.pow(v, 4).div(100**3);
+            if (Decimal.gte(v, 100)) v = Decimal.pow(v, 4).div(100 ** 3);
             v = Decimal.pow(0.95, paper.books.heavyDrillBook.totalAmount.value).times(v);
             return Decimal.pow(1.3, v).times(2.5e4);
         },
         inverseCost(x: DecimalSource) {
             let v = Decimal.div(x, 2.5e4).log(1.3);
             v = v.div(Decimal.pow(0.95, paper.books.heavyDrillBook.totalAmount.value));
-            if (Decimal.gte(v, 100)) v = Decimal.mul(v, 100**3).root(4);
+            if (Decimal.gte(v, 100)) v = Decimal.mul(v, 100 ** 3).root(4);
             return Decimal.isNaN(v) ? Decimal.dZero : v.floor().max(0);
         },
         display: jsx(() => (
@@ -165,14 +165,14 @@ const layer = createLayer(id, function (this: BaseLayer) {
         resource: metal.metal,
         cost() {
             let v = new Decimal(this.amount.value);
-            if (Decimal.gte(v, 50)) v = Decimal.pow(v, 4).div(50**3);
+            if (Decimal.gte(v, 50)) v = Decimal.pow(v, 4).div(50 ** 3);
             v = Decimal.pow(0.95, paper.books.heavyDrillBook.totalAmount.value).times(v);
             return Decimal.pow(2, v).times(1e5);
         },
         inverseCost(x: DecimalSource) {
             let v = Decimal.div(x, 1e5).log(2);
             v = v.div(Decimal.pow(0.95, paper.books.heavyDrillBook.totalAmount.value));
-            if (Decimal.gte(v, 50)) v = Decimal.mul(v, 50**3).root(4);
+            if (Decimal.gte(v, 50)) v = Decimal.mul(v, 50 ** 3).root(4);
             return Decimal.isNaN(v) ? Decimal.dZero : v.floor().max(0);
         },
         display: jsx(() => (
@@ -227,14 +227,16 @@ const layer = createLayer(id, function (this: BaseLayer) {
         resource: metal.metal,
         cost() {
             let v = new Decimal(this.amount.value);
-            if (Decimal.gte(v, 10)) v = Decimal.pow(v, 4).div(10**3);
+            if (Decimal.gte(v, 10)) v = Decimal.pow(v, 4).div(10 ** 3);
+            if (Decimal.gte(v, 1e3)) v = Decimal.pow(v, 4).div(1e3 ** 3);
             v = Decimal.pow(0.95, paper.books.heavyDrillBook.totalAmount.value).times(v);
             return Decimal.pow(8, v).times(2e5);
         },
         inverseCost(x: DecimalSource) {
             let v = Decimal.div(x, 2e5).log(8);
             v = v.div(Decimal.pow(0.95, paper.books.heavyDrillBook.totalAmount.value));
-            if (Decimal.gte(v, 10)) v = Decimal.mul(v, 10**3).root(4);
+            if (Decimal.gte(v, 1e3)) v = Decimal.mul(v, 1e3 ** 3).root(4);
+            if (Decimal.gte(v, 10)) v = Decimal.mul(v, 10 ** 3).root(4);
             return Decimal.isNaN(v) ? Decimal.dZero : v.floor().max(0);
         },
         display: jsx(() => (