Recent days have ushered in the "Frostmancy" strategy, where solo laners take Kleptomancy and Spellthief's Edge to harass their opponent with Tribute procs and maintain their income with Kleptomancy while ignoring last hitting. This strategy throws several laning skills out the window, erases the gold tradeoffs for missing last hits, and gives opponents no means of interfering with your plan.
Similar to gold funneling last season, we're taking a heavy-handed approach to remove Frostmancy now while we work on a more refined long-term solution. Since this change hits some legitimate support decisions (ex. staying in lane while your carry recalls) we're increasing Tribute gold a bit to avoid big nerfs to Spellthief's' intended users. We're applying the same philosophy to Ancient Coin as well to avoid the risk that Frostmancy users simply rotate off Spellthief's onto Coin.