What is the correct Latin translation for the phrase, "He Who Is Without Mercy" ?

I have to write some of my own Latin phrases for a project I'm doing, but I'm terrible with Latin, and I can't hardly find a correct translation site. Anyone wanna help, please? D8|||If you're referring to a specific person who is currently acting without mercy:





is qui clementia caret





lit. "he who is (presently) lacking mercy".





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"caret" is 3rd person singular indicative of "careo" = "to be void/free from; to lack/need"; together with "qui", forms a simple relative clause; Note that "careo" takes the ablative for its object, i.e. "clementia".





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If you're generalizing a kind, or type, of person, i.e. one (of others) who would act without mercy:





is qui clementia careat





lit. "he who would be the sort of person to lack mercy".





"careat": 3rd person singular present *subjunctive*; together with "qui" forms a generic qui clause (a.k.a. relative clause of characteristic);





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Compare:





Indicative:





is, qui clementia caret, omnes interficit


"he, who is showing no mercy, kills everyone".





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Subjunctive:





is, qui clementia careat, inimicos modo habet


"a person that lacks mercy has only enemies"





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You can also use a participle, esp. for titles:





ille clementia carens





cf. (from Harrius Potter) "Nick Paene Capite Carens" = "Nearly No-Neck Nick"