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Maybe two ways to "fix" what may or may not be considered a problem.
1. Engine Upgrade is errata'd to be small ship only. Unambiguous but probably unlikely.
2. Cause large ships to boost using the flat side of a maneuver template Unless that ship comes with boost on its action bar. So EU on large base ship becomes a smaller bump and cannot be used to change direction.
So how terrible an idea is it? I'm sure the answer depends partly on how often you plan on running a large ship with Engine Upgrade.
Option #1 is pretty much something that should NEVER happen. When the only way to get it is currently from large ships it would be a crime to say they couldn't use it themselves.
I'm not sure how option #2 is supposed to work.
IF it needs to be change I think I've seen two ideas I could support.
One is that instead of placing the template inside the guides you place it outside of the guides. If banking the template goes opposite the back to make it shorter. If straight then I guess you'd use the edge of the template a little like how BR now works with large ships.
The easier one to explain, but possibly harder to execute, is that instead of using speed 1 templates you use speed 2 templates BUT instead picking the ship ship up and moving it so the back guides line up with the template you have it so that the front guides only move the length of the template. The problem is that this places the ship on top of the template so that another marker in needed to mark the ship's position while the maneuver template is removed. This means that when a small ship moves the front of the ship basically moves 2 'units' of distance which would match up with a large ship's nose moving 2 "units" of distance when using the RAW they move 3 units of distance.
Coming soon: X-Wing DiskWars!

