When I look at Unfathomable Truths from Modern Horizons 3 , it engages both my imagination as a viewer and my technical mind as a painter
Players who put in overtime at work to be able to afford that last dual land, long-time players who considered their collection to be something of a nest egg, people who convinced their spouses that these Reserved List cards were a good investment as well as a fun weekend hobby
So you can do this at any time, transferring the +1/+1 counter and the Buster Sword to Cloud
Just dont be surprised if you become the threat once opponents learn you run this card, whether its anywhere near the battlefield at the time or not
That's a very powerful ramp effect, usually seen on green cards like Dryad of the Ilysian Grove
The application that keeps coming to mind is avoiding end-of-turn stuff that you would prefer not happening, like with Final Fortune