The term 'LIGHT INTO' can be completed with the following crossword solutions: LAMBASTE (8 letters), ASSAIL (6 letters), RIP (3 letters), LASHAT (6 letters), ASSAULT (7 letters), SHOUTAT (7 letters), and REPROACH (8 letters). All of these words refer to a type of verbal or physical attack, and they are all synonyms for the phrase 'light into, ' which is an informal expression meaning to criticize or attack someone or something.