Primal Rampage — prehistoric survival wave shooter

Vanilla JS + Canvas 2D, zero dependencies.

Gameplay: campaign waves vs 12 dino species + 3 bosses, arena mode,
7 weapons, hero talents, pets, ult/bombs, card roguelite picks.
World: day/night cycle, weather fronts (rain+lightning), Blood Moon
weekends, 3 act biomes (jungle -> swamp -> ashlands with lava veins).
Meta: gems economy, upgrade tree, quests, bestiary, achievements,
shop (weapons/heroes/skins incl. premium), revive, ad-cap system,
endless scaling past wave 25, live-painted shop/bestiary icons,
pro main menu, auto-aim toggle (F). Headless smoke suite included.

js/util.js

@@ -0,0 +1,13 @@
+/* Neon Rampage — small shared utilities. */
+(function () {
+  'use strict';
+  var US = (window.US = window.US || {});
+  US.util = {
+    rand: function (a, b) { return a + Math.random() * (b - a); },
+    randInt: function (a, b) { return Math.floor(a + Math.random() * (b - a + 1)); },
+    pick: function (arr) { return arr[Math.floor(Math.random() * arr.length)]; },
+    clamp: function (v, a, b) { return v < a ? a : v > b ? b : v; },
+    dist2: function (ax, ay, bx, by) { var dx = ax - bx, dy = ay - by; return dx * dx + dy * dy; },
+    fmt: function (n) { return String(Math.floor(n)).replace(/\B(?=(\d{3})+(?!\d))/g, ','); }
+  };
+})();