Like most Pokmon cards, the value of Psyduck depends on a few consistent factors: its rarity, the printing and finish (regular or foil), its physical condition, and the set it was printed in (Detective Pikachu)
It can move any kind of counters, and isnt locked to one player, so you can throw some -1/-1 counters at an opponent, or snatch their +1/+1 counters for yourself
Due to the games advanced graphics (with some 2.5D environments), its only playable on the GBC
Searching for the best Pokmon packs to buy for profit was something I never thought would seriously happen back when I was a kid
By default the phase indicator just lets you move cards around as you will, skipping certain portions of each turn in an effort to speed up play