An Aura controlled by another player does not cause a creature you control to be modified
But cipher allows for repeatedly tapping creatures can be useful alongside effects like Royal Assassin
There are some interesting parallels to Tireless Missionaries, among other cards
In the case of Time Walk, it retained its devastating ability: take an extra turn for just two manaone of the strongest effects in the entire MTG game
Im absolutely certain that testing for this kind of stuff is pretty much impossible to do, but with Companions being overwhelming a while ago, and a slew of other bannings and missteps in the last year or so, it can really feel as though things are going wrong
I like what they tried in the WHO expansion from Universes Beyond, where The First Doctor is xxx/501 and The Thirteenth Doctor is xxx/513, but the demand for those cards as Commanders hasnt materialized