hello. today im pvp and got a bug. In the picture. ferro used power whip to attack my pelipper when 50% hp and down to 10% hp, after that, my bird used roost go up to 60% hp, and ferro used power whip again and got super effective. my bird dead. Can someone help me explain this situation?, 
Thanks! 

Hello @Dnler.

 

This is not a bug, but rather the intended way Roost is supposed to function.

When a Flying type Pokémon uses Roost, it will lose the Flying type for that round. Since Pelipper, a Flying type, used Roost, it lost the Flying type for that round and was pure Water type. Thus, Power Whip was super effective.

You can read more about Roost here.

If you have anymore questions or if you would like further clarification, please let me know.

Just now, Epithet said:

Hello @Dnler.

 

This is not a bug, but rather the intended way Roost is supposed to function.

When a Flying type Pokémon uses Roost, it will lose the Flying type for that round. Since Pelipper, a Flying type, used Roost, it lost the Flying type for that round and was pure Water type. Thus, Power Whip was super effective.

You can read more about Roost here.

If you have anymore questions or if you would like further clarification, please let me know.

i checked, this my mistake. thanks for reply me.

Locked as resolved.

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