Answer by taking a quote from the following article:

Earth Crisis is an American metalcore band from Syracuse, New York, active from 1989 until 2001, reuniting in 2007. Since 1993 the band's longest serving members are vocalist Karl Buechner, guitarist Scott Crouse, bassist Ian Edwards and drummer Dennis Merrick. Their third guitarist Erick Edwards joined the band in 1998. The band has released eight studio albums, three compilations, two live albums and six music videos.

Although ideologically tied to the straight edge movement, the initial musical influences of Earth Crisis were mainly from New York hardcore bands such as Agnostic Front, Cro-Mags and Sick Of It All. After the All Out War EP, they developed an increasingly technical and heavier style, citing death metal bands Napalm Death, Bolt Thrower and Obituary as prime inspirations. Buechner's vocals became rougher with each release as well, culminating in the completely gutturally screamed Gomorrah's Season Ends. Terrorizer magazine referred to this album as "heavy hardcore taken to a new level, all the blackness that was hinted at on Firestorm realized in all its formidable glory." In this period, many of their songs were built on Merrick's drum beats.  Their third studio album, Breed the Killers, maintained the previous aggressiveness and its growled vocals were "taken about as far as possible", but it followed a structure more akin to the "post-Judge hardcore of the Path of Resistance record Who Dares Wins", according to Shawn Macomber of Decibel. Dennis Merrick said: "On Breed the Killers I think we achieved the most honest representation of our sound without sounding too raw or too slick". Its follow-up, Slither, had a change of style that steered towards nu metal. Buechner declared that, rather than being influenced by other styles, they "resurrected" the sound of All Out War in a proper way, which also had melodic choruses and spoken word verses.  Their first post-reunion album, To the Death, was described by Buechner as "a mixture between Destroying the Machines and Breed the Killers." According to Stereo Killer, it was "arguably the band's heaviest offering" but with "more traditional verse/chorus/verse" material. Neutralize the Threat followed a similar path, but "with a Gomorrah's Season Ends vibe thrown in", the band stated. Scott Crouse said that he always tried "to get the perfect blend of heaviness, imagery and listenability" and that these two albums were the first to "hit that mark". Salvation of Innocents included, in addition, some clean vocals that were compared by one reviewer to the sludge metal band Crowbar, as well as "some elements of European melodic metalcore" and faster songs.  When asked what ten bands inspired Earth Crisis over the years in a 2016 interview, Scott Crouse named DYS, Judge, Corrosion of Conformity, Agnostic Front, Slayer, Sepultura, Metallica, Conviction, Zero Tolerance and Iron Maiden.

did they have any other influences?
they developed an increasingly technical and heavier style, citing death metal bands Napalm Death, Bolt Thrower and Obituary as prime inspirations.