When looking for synonyms to replace the phrase "set against," there are plenty of options to choose from. Some common alternatives include "opposed to," "anti," "disapproving of," "averse to," and "unfavorable towards." These phrases all convey a sense of disagreement or negativity towards something or someone. Other synonyms include "critical of," "objecting to," "hostile to," "resistant to," "unsympathetic to," and "contrary to." Each of these phrases can be used to describe a person's stance on an issue or their attitude towards another person. By using synonyms for "set against," you can communicate your ideas in a more nuanced and expressive way.