If I play multiple spells that add up to four energy, do I get the effect with Jhin Meticulous Killer?

To answer your question: No, you must spend [4] or more energy to play a single spell in order to trigger the alternative cost for Jhin, Meticulous Killer.

According to the card text: "If you've spent [4] or more to play a spell this turn, you may play me for [C]."

Key Clarifications:

• "A spell" vs. "Spells": The ability specifically checks the cost of a single spell instance. Spending energy across multiple spells to reach a total of [4] does not satisfy the condition "to play a spell."
• Total Cost vs. Base Cost: As established in RiftJudge FAQ #10012, if a spell has an additional cost (like the [Repeat] keyword or other additional costs), that cost counts toward the total energy spent to play that specific spell. If the total energy spent on that single spell is [4] or more, you qualify for Jhin's alternative cost.
• Countered Spells: Per RiftJudge FAQ #9920 and the associated 2026-04-29 Rules FAQ Clarification, Jhin checks if the energy was spent and the spell became a "Finalized Chain Item." It does not matter if the spell resolves or is countered later; if you spent [4] or more on that one spell, the condition is met for the rest of the turn.

In summary, you cannot combine the costs of several separate spells to trigger this ability. You must play one spell that costs [4] or more (inclusive of additional costs).