1) Act hostilely 2) Attack 3) Attack first 4) Draw first blood 5) Move 6) Set upon 7) Start a war 8) Strike first 9) To begin to quarrel 
• (v. i.) To commit the first act of hostility or offense; to begin a quarrel or controversy; to make an attack; -- with on. • (v. t.) To set upon; to attack. • (n.) Aggression.
Ag·gress' intransitive verb [ imperfect & past participle Aggressed ; present participle & verbal noun Aggressing .] [ Latin aggressus , past participle of aggredi to go to, approach; ad + gradi to step, go,...Ag·gress' noun [ Latin aggressus .] Aggression. [ Obsolete] « Their military aggresses on others. Sir M. Hale. » Ag·gress' transitive verb To set upon; to attack. [ R.]
verb take the initiative and go on the offensive; `The Serbs attacked the village at night`; `The visiting team started to attack`
to commit the first act of hostility or offense; attack first. · to begin to quarrel.