In a clause you’d first name the “unforeseen cascading effects” of a spell, then set a limit—say, a maximum amount payable if an unintended chain reaction causes damage. You’d also require the caster to take “reasonable precautions” like setting containment boundaries and having a backup spell ready. Finally, add a “no-fault” provision for purely accidental misfires, so both sides know the risk is shared, and the contract can be renewed once the spell’s parameters are fully understood.

You’re right—let’s spell out those precautions. I’d list concrete steps: use a spell‑buffer radius of at least ten meters, keep a counter‑spell ready, and conduct a pre‑flight test with a low‑level rune. That gives anyone reading the clause a clear yardstick. And I’ll add a line that the “no‑fault” clause only applies if the caster followed those steps; otherwise, professional negligence still triggers liability.

Clause 3.3 – Unforeseen Cascading Effects The caster shall implement the following precautionary steps to mitigate unintended chain reactions: 1. The spell‑buffer radius shall be established at no less than ten meters from the spell’s epicenter; 2. A ready counter‑spell must be maintained, capable of neutralizing the primary spell within the buffer zone; 3. A low‑level rune test shall be conducted prior to deployment, ensuring the spell’s behavior conforms to the prescribed parameters. Each numbered step is referenced in the liability limits of Clause 3.3, and the caster is deemed to have met reasonable precautions only if all three steps are executed as described. Appendix A – Definition Spell‑buffer radius: The spatial zone, measured in meters, surrounding the point of spell origin where unintended secondary effects are expected to be contained. The radius shall be maintained at a minimum of ten meters unless an alternate containment method is approved by the governing body.