There are two common methods you can utilize to do this
Spellseeker Perhaps best known for finding Time Walk in Vintage Cube and Canadian Highlander, Spellseeker is one of those situational cards that excels when you have high value, low-cost instants or cards like Brain Freeze, but it does little without them
Loot, Exuberant Explorer, Bloodbraid Challenger, Ilharg, the Raze-Boar, and Emergent Woodwurm are all great at sneaking creatures into play without even paying for them
This is because of the update frequency between what's shown in the app and what you can see in the store's website
Light The Fuse lets you deal 1 damage to a chosen character for each exerted character you have in play, while The Sword of Shan-Yu has you exert a character to then ready another chosen character
So, I wanted to communicating "Trader" with just a hint of "Traitor" in her design