When it comes to synonyms for the phrase "render difficult," there are several options to choose from. Some of the most common synonyms include "complicate," "perplex," "confuse," "obstruct," "hamper," and "hinder." Each of these words can be used to describe a situation where something is making a task or process more challenging than it needs to be. For example, if someone is trying to navigate a complex maze, they might say that the twists and turns of the maze are rendering their progress difficult. Overall, these synonyms capture the idea of making something harder than it should be and help to communicate the frustration and struggle that often comes with difficult tasks.