Present participle; Past participle - havocking - havocked Present - havoc - havoc - havocs - havoc - havoc - havoc Past - havocked - havocked - havocked - havocked - havocked - havocked Future - will havoc - will havoc - will havoc - will havoc - will havoc - will havoc Present conditional - would havoc - would havoc - would havoc - would havoc - would havoc - would havoc Present Perfect - have havocked - have havocked - has havocked - have havocked - have havocked - have havocked Past Perfect - had havocked - had havocked - had havocked - had havocked - had havocked - had havocked Future Perfect - will have havocked - will have havocked - will have havocked - will have havocked - will have havocked - will have havocked Past conditional - would have havocked - would have havocked - would have havocked - would have havocked - would have havocked - would have havocked Imperative - - - havoc - - - - - - - -