So if you're merging Cities because you want to get a single high population one, then this strategy is considerably less useful. The only downside that it comes with is the fact that it takes a lot of time, needs a military Unit, and it also kills off all of the Population and deletes the Infrastructure of the City that's getting destroyed. This strategy needs far less Influence, turning a cost of tens of thousands to only a few thousand at most. Afterward, you can simply attach the Outpost to your City, which will have a lower cost than merging a City. Because the Outpost is created on top of Ruins, it will be established immediately. Once the City is destroyed, you can create an Outpost in the same spot as the ruins of the City.

However, there is a far cheaper solution to the high costs of merging Cities - simply burn one of the Cities to the ground! Take a military Unit and start ransacking a City. While this cost can be reduced in some ways (making sure that both cities have identical sets of Infrastructure can reduce the cost), it will still be rather expensive, and merging Cities will usually cost too much Influence for a fairly low return.

It isn't uncommon to see the Influence needed to reach the tens of thousands, which is oftentimes far too much Influence than can be afforded. At the moment, the Influence needed to merge Cities together can very easily reach prohibitively high costs.

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