There are other less-seen Pokmon with Abilities and Pok-Bodies that affect Retreat Cost, and Ill go over them only to get the rules covered
Overall, there are plenty of ways to disrupt the opponent's hand, and some of them are more permanent, but Iono is the most efficient way of doing so
The best way is to use a Pokmon card value checker like Rare Candys scanner and tracker, which gives you real-time data
Three mana for a hard-to-cast Night's Whisper or a few +1/+1 counters aint doing it, but as we know, the strength of these charms is their modality and ability to adapt to the way the games developed
Our proxies are great alternatives for copies of those expensive cards that you own and players looking for alter art to use as their Commander, cube, EDH and CEDH games
How you build the deck based on your other creature type is up to you