Ursulas mindset, for example, is a different vibe than Peter Pans, so you approach that differently in terms of shapes and gestures, and what a particular character is supposed to convey
She allows you to draw cards by removing hit counters from creatures in exile whenever your assassins, mercenaries, and rogues deal combat damage to a player, effectively allowing them to collect on the rewards for carrying out these contracts
Ramp hard with Elf mana dorks, swing with Lathril to create tokens, then tap ten Elves to drain ten life from each opponent in one shot
Its mostly in the fun tier for the flavor of getting protection from Assassins and is a massive lord for Knights
For a look at some of the more complex barriers, check out this article on a group making the Pokmon TCG more accessible for minority gender fans.
This replacement effect applies across cards so if you have Shark Typhoon out, you get 8/8 octopus instead