diff --git a/engine/system/physics.ts b/engine/system/physics.ts
index 69edbaa..ce42069 100644
--- a/engine/system/physics.ts
+++ b/engine/system/physics.ts
@@ -7,6 +7,7 @@ import {
 	getDistance,
 	getDotProduct,
 	invScale,
+	scale,
 	setUnitNormal,
 	type Vector,
 } from "#/engine/Vector.ts";
@@ -283,8 +284,17 @@ export function moveAndSlide(
 ): void {
 	const collisions = moveAndCollide(id, velocity, delta);
 	for (const collision of collisions) {
+		const time = collision.time;
+		if (time === -Infinity) {
+			continue; // TODO
+		}
 		const dot = getDotProduct(velocity, collision.normal);
-		velocity.x -= collision.normal.x * dot;
-		velocity.y -= collision.normal.y * dot;
+		const ts = Math.min(0, time - 0.001);
+		const tsx = velocity.x * ts;
+		const tsy = velocity.y * ts;
+		const rt = 1 - time;
+
+		velocity.x -= collision.normal.x * dot * rt + tsx;
+		velocity.y -= collision.normal.y * dot * rt + tsy;
 	}
 }
diff --git a/game/entities/hero/entity.ts b/game/entities/hero/entity.ts
index d38b781..de1ae9a 100644
--- a/game/entities/hero/entity.ts
+++ b/game/entities/hero/entity.ts
@@ -1,6 +1,5 @@
 import { defineEntity } from "#/engine/Entity.ts";
 import { keyboardInput } from "#/engine/Keyboard.ts";
-import { lerp } from "#/engine/lib/lerp";
 import { pointer } from "#/engine/Pointer.ts";
 import { createRect, fillRect, strokeRect } from "#/engine/Rect.ts";
 import $ from "#/engine/Scene.ts";
@@ -11,15 +10,12 @@ import {
 } from "#/engine/Sprite.ts";
 import {
 	type Collider,
-	type Collision,
 	createCollider,
-	moveAndCollide,
 	moveAndSlide,
 	Shape,
 } from "#/engine/system/physics.ts";
 import {
 	createVector,
-	getDotProduct,
 	normalize,
 	scale,
 	type Vector,
diff --git a/game/scenes/testScene/data.json b/game/scenes/testScene/data.json
index e52001d..8396e84 100644
--- a/game/scenes/testScene/data.json
+++ b/game/scenes/testScene/data.json
@@ -12,6 +12,15 @@
 				}
 			}
 		},
+		{
+			"name": "portal",
+			"init": {
+				"position": {
+					"x": 24,
+					"y": 41
+				}
+			}
+		},
 		{
 			"name": "portal",
 			"init": {