I'll analyze Scapeshift's current performance in Pioneer to see if the data supports this concern.
The data tells a different story. Simic Scapeshift is currently a niche deck in Pioneer, not the dominant force you're describing. Over the last 30 days, it represents just 3% of the metagame with only 16 tournament entries. While its 64.4% winrate is notable, this is from a very small sample size of 47 matches. For comparison, the actual metagame leaders are Mono Red Aggro at 21% presence and Rakdos Midrange at 12%.
Looking at trends over the past two months, Scapeshift has fluctuated between 1-4% presence with winrates ranging from 50% to 67% week-to-week. The deck saw a spike in late September/early October but remains far from format-defining. Mardu Greasefang, another combo deck with similar sample size, also shows 64% winrate, suggesting these numbers may reflect skilled pilots rather than format warping power.
The concern about dominance doesn't match current tournament results. Scapeshift is performing well when piloted but isn't showing the presence or consistency that typically prompts action.
Sources
Data from 19 Pioneer tournaments (84% MTGO, 16% Melee) between September 16 and October 16, 2025.
https://www.mtgo.com/decklist/pioneer-challenge-32-2025-10-1212819543
https://www.mtgo.com/decklist/pioneer-showcase-challenge-2025-10-1212819892
https://www.mtgo.com/decklist/pioneer-challenge-32-2025-10-1112819530