Nyxbloom Ancient + Doppengang can cause integer wrapping bugs
I played Oko’s 5 loyalty ability to copy a Nyxbloom Ancient, then Doppelgang to copy both copies 5 times. This meant each mana I produced should have been multiplied by 3^12 (about 500,000). I also had a Kinan out, which I guess makes than 1 million. (Or 1.5 million for a 2-mana tap.)
Instead, I got around 212 mana from tapping for one mana, and 4375 for tapping for 3. These numbers don’t make any sense.
It would be better to cap the number of mana at something like 100 when there’s an overflow.
Also the performance of casting spells and activating abilities was terrible. If the game can’t cope with that many objects, it should just not create them. It wouldn’t have mattered anyway.