Prior to co-founding Shadows Fall with fellow guitarist Matt Bachand in 1996,[5] Donais was a member of metalcore band Aftershock from 1993 to 1997,[4][6] which morphed into Killswitch Engage, although after his departure.

[7] Shadows Fall's first line-up included Donais and Bachand alongside Damien McPherson (vocals), Mark Laliberte (bass), and David Germain (drums).

By late 1996, the band recorded and released a demo titled Mourning a Dead World, of which only about 200 copies were produced.

[5] It consisted of the songs Lifeless, Suffer the Season, Fleshold, Forever Lost, A Souls Salvation, and Deadworld.

Around the same time, bass guitarist Paul Romanko, formerly of the hardcore band Pushbutton Warfare, was recruited as a permanent replacement for Laliberte, who had originally joined on a temporary basis.

[5][8] Now with a more solid lineup, the band released its first EP, To Ashes, with Aftershock member Adam Dutkiewicz playing as a session drummer.

[10][11] On June 22, 2021, vocalist Brian Fair confirmed that Shadows Fall were reuniting for their first show in over half a decade at the Worcester Palladium on December 18.

"[21] Donais is also a member of supergroup Living Wreckage which is composed of Donais, vocalist Jeff Gard (Death Ray Vision), guitarist Matt LeBreton (Downpour), bassist Matt Bachand (Shadows Fall, Act of Defiance) and drummer Jon Morency (Let Us Prey),[22] the band came about during COVID-19 pandemic and was composed of musicians who lived near each other so "we could get in the basement once a week and just do it the old school way of, you know, having some beers, jammin and just having fun with friends.

"[22] The bands music is a cross between thrash metal and arena rock, like "Skid Row, Tesla, the mainstream MTV stuff that was in the eighties.

"[22] Donais main influences are guitarists Zakk Wylde (Black Label Society) and Dimebag Darrell (Pantera) (both of which he has toured with),[23] Randy Rhoads (Ozzy Osbourne), James Hetfield (Metallica), Warren DeMartini (Ratt), John Sykes (Thin Lizzy, Whitesnake) and Alex Skolnick (Testament).