DUEL
I've seen players fight and challenge each other in other games or here?

I don't know the whole PVP rules yet or how it looks, but add a feature where you can challenge someone to a duel? (Players can turn this feature on or off, upcourse.)

If accepted, the challengee will pick a map of his or her preference. And It will be flashed on other players' screen, there is waiting time, that moment players who click and want to watch them duel can bet silvers? Players then can watch the duel and win silvers or additional prices.

Add in settings a 1 vs. 1, 2 vs. 2, 3 vs. 3, 5 vs. 5 or 10 vs. 10 duel.

Player main chara and their other chara (Auto) fights vs. the other player's and his other picked chara.

If the main chara dies, he / she can pick other chara or random? Until there is none.

Players can use the feature once a day or week? Or sell a duel coupon for players to use the feature in black pearls.

Spectators can only bet on one player (Family).

Add a feature to gift your picked player so win or lose they receive that gift, example a token to use in the store?

This will inevitably scar the losers forever.
- Gomez Addams, The Addams Family 2 (Cartoon movie)
Me: Perhaps? Mr. Addams, perhaps. This idea should be scrapped then.

TOURNAMENT
GM can use this feature to arrange a tournament... Players will receive a coupon then upon use their family name will register in the tournament. Or any means to register easily upon announcement?

The system then arrange those players by cp upon successfully closing the time to join the event. Or purely random?

Accepted players then wait and fight.
In this waiting time... Players who did not participate can bet, their bet will be multiplied by something or doubled each time their picked player wins.

Or will receive a gift for betting, players who participated and fought has various gifts too, depending on their number of wins or place in the tournament.

Player's then need to win a certain number or if lose twice? Or a certain number he / she will be eliminated in the tourney.