Snowfield Sinkhole

The tapland-with-a-basic-type template, run through a snow filter. What it buys you is dual-color fixing that reads as both a Plains and a Swamp, so it fetches, triggers, and counts as either basic land type despite being neither basic nor a single color. The cost is spelled out in the entering-tapped clause: a full turn of tempo, paid up front, which is the standard tax this style of untargeted dual has carried since the earliest common-rarity duals used it to keep fixing off the first few turns of aggressive play. Where it diverges from the older tapped duals it otherwise clones is the snow line on its type: snow is a resource other cards track, so this is fixing that doubles as fuel. It feeds effects that scale with snow permanents or demand snow mana specifically, and it does so while still producing two colors, unlike the snow basics that force you to choose a single color per source. That is the whole trade. You accept the tapped turn, and in return you get a dual that pulls double duty as a snow source, an upgrade over a comparable non-snow tapland only in decks built to notice the difference.