Humble is perfect in this deck, because you can Pestilence any creature Humble can target, including those with an ability that would normally keep them alive (such as protection)
It's the second-most popular blue card, full stop, behind only CounterspellCounterspell, and it's the single-most popular enchantment of all-time (regardless of color) based on both volume and percentage
Whether it is the right tool for you, in a deck you build or in a game, is largely going to be a function of what is useful for you at the time
So, let's go deep into the forest and find some fungi
The Fairy type was retired in 2020 for new sets, though older cards retain the type
Good as a way to get a few problem cards out of the picture before they do any damage and good as a way of throwing a spanner in the works of what your opponent is up to but not something to rely on to lock someone out of the game or solve every problem