For categories that allow or require use of legacy heroes, I believe it would be beneficial to the community and to fair competition to allow cheats and save file editing outside of submitted runs for the purpose of character creation and legacy aspect modification as long as the resulting characters would be able to be created through fully legitimate gameplay.

• It would lower the barrier to entry: Due to the legacy system, there can be huge differences in effectiveness based on what heroes are present in that profile’s legacy. With the current restriction, to have a chance to be competitive in a category that allowed or required legacy heroes, a player would probably have to spend at least several hours re-rolling stats and events per hero before even getting to the speedrunning practice. This may not be a huge amount of time compared to doing many attempts of the runs themselves, but I think it would noticeably increase the barrier to entry. Using cheats to pick events and skip battles (if it doesn’t cause missing an important victory event) would speed this up considerably. Additionally, if a player wanted to make a minor change to an existing hero that is not possible through normal gameplay but could have been done through normal gameplay if the hero had been built differently (for example, many cases of removing wings from a hero), using devMode to make the change would likely be much faster than recreating the hero from scratch.
• It would encourage sharing resources: Since a player cannot know whether another player’s hero was created with cheats, they would not be able to use heroes from other players under the current rules. 
• It would prevent longtime players from having a permanent advantage of newer players: The current rules would allow players who already have fully legitimately created legacy heroes with persistent versions of Clearbody, Symbiont, Vitality, Slacker’s Charm, and/or Slacker’s Resolve to have a permanent advantage over players who do not. These heroes were able to be created before patch 1.9 and those buffs still persist through legacy as of 1.16+554 if added to a hero in 1.8 or earlier. New players, or players who did not legitimately create these heroes while it was possible, would not have access to them under the current rules.
• It has precedent in other communities: For example, in the Borderlands 2 “UVHM Geared” category, another situation where the existing save is very relevant to performance, the savefile must be “legitimately obtainable”, not necessarily legitimately obtained. (Reference: https://www.speedrun.com/bl2?h=UVHM_Geared-co-op&rules=category&x=jdz9le32-j846oq2l.rqvwkky1)

One related issue is that the event weighting system in Wildermyth makes it so recently seen events are less likely to be seen again (https://wildermyth.com/wiki/Event#Event_types). These deviations from default weights are stored in the legacy file. This makes it so even if two players attempted the same campaign with the same heroes, they most likely have a different set of probabilities of seeing each event, which seems less than ideal. On the other hand, I also don’t think it would be good to require a 3rd party tool that resets the weight modifications. Alternatively, allowing players to edit (or use normal gameplay to adjust) the weight modifications so that all the events except the ones they want to see have heavily reduced probabilities doesn’t seem very good either. This topic may be better discussed in a separate thread. (There is also dynamic weighting for how Omenroad bosses are chosen (although it works a bit different than for regular events). There are no Omenroad challenge run categories yet, but when/if they are added, there will be a similar challenge in making runs more fair there.)

What do people think about these? 

(I can split the topics into multiple threads if that would be more appropriate.)