Best cards to counter late game commander decks

I've been theory crafting a deck recently that's a mixture of merfolk and technically stax. The goal of it is to keep everyone in the game from playing expensive cards by restricting lands and destroying high power creatures and lands with board wipes. Right now I have Sygg, River Guide as the commander, which gives my merfolk some protection from the hate I expect to get from people playing later game decks like eldrazi.

Point is I'm looking for cards that specifically restrict or target higher cost cards. My colors are blue and white, does anyone have any suggestions?