Sure thing! Think of each spell as a tiny contraption you build in the moment. Start by giving every spell a clear “fuel” – maybe a mana pool, a word of power, or a ritual step. That’s the cost. Then decide what the spell does and add a built‑in limitation or side effect – a leak in the engine, a heat‑up, or a counter‑spell that could fire back. That keeps the magic from being all‑or‑nothing and gives players a chance to weigh risk versus reward. Next, make a simple rubric: cost, effect, duration, and risk. If a spell is huge, bump its cost or risk level. If a spell is cheap, make it less powerful or narrower in scope. Players can tweak by adding modifiers – a clever bard might add a “focus” card to lower the cost, while a reckless wizard might double the effect at double the risk. Keep the epic feel by letting those limits explode in the right moments. A spell that normally does 3 damage could, when pushed to its limit, do a cascade of fire that lights a whole battlefield. The players still feel the thrill of the unknown, but the rules keep the game balanced. So, build each spell like a machine: clear inputs, defined outputs, a safety valve, and a chance for an unexpected twist. That way the wild magic stays wild, but the system stays tight.

I love the idea of a safety‑net that’s also a surprise, so let’s tweak the rubric a bit. First, make every modifier a wild card: instead of a clean “+2 to damage,” it could read “roll a die; if it’s a 1, the spell backfires, if it’s a 6, the spell explodes for double damage.” That keeps the tension high. Second, have the “focus” card be a flip‑flop – it can either lower the cost or trigger a random side effect. For example, a focus of “Silence” might silence the caster for a round instead of saving mana. Third, build a quick check into the rulebook: when a player stacks two high‑impact modifiers, the DM rolls a “balance check” before the spell resolves. If the result is too high, the spell fizzles or splits into two weaker effects. That way, the system watches itself, but still lets the chaos dance. Keep the rules light, let the surprises be the real drama.