Selecting shiny Tapu Koko in the team builder results in an error message that states:
"Your team was rejected for the following reasons:
- Tapu Koko is only obtainable from events - it needs to match one of its events, such as:
- Tapu Koko must not be shiny to be from its event #1."
This is wrong for two reasons. 1: Because Tapu Koko is NOT only obtainable from events. It is available in game after beating the Elite 4. 2: Because its only event distribution so far was for a SHINY Tapu Koko. Back in February, if I recall correctly. Maybe March. But the when is irrelevant. Point is, it's legal, and I've seen shiny Tapu Koko used on Showdown since then so idk how recent this bug is. But it's site wide, not just on the main server. To make sure it wasn't a move or ability issue, I tried it with only thunderbolt and both abilities. Same issue, but with it saying its hidden ability is unreleased when I tried it with that (which I believe is accurate). So it's not a move or ability incompatibility issue, it's simply incorrect.