Cefni trailed 3-0 and 4-2 yet fought back to draw 4-4 and then beat Boded on penalties to advance to round two of the Trophy.
When the draw was made, this all tier-5 Anglesey derby bore the hallmark of one of the ties of the round and so it proved in front of a large crowd at Isgraig, Llangefni.
Boded looked in command after Jenson Rowlands put them 1-0 up on 12 minutes, then Alfie Dodds doubled the lead from a Chris Jones assist after 25.
It got better for the visitors when Rhys Thomas set up Chris Jones to make it 3-0 to the greens after 57 minutes.
Cefni threatened to launch a comeback when Dylan Griffith opened their account on 68 minutes and soon after Tal Huws cut the deficit to 3-2.
Chris Jones scored again for Boded on 85 and now the away team appeared to have one foot firmly in the second round.
However, things started to go wrong for the visitors when Jordan Taylor was red-carded after 88 and a minute later a Ryan Heywood own goal made it 4-3.
Six minutes into added time, up popped Cefni striker Dion Jones to level the match and send the Isgraig faithful into raptures.
It came down to penalties and Cefni keeper John Glyn Roberts emerged the hero, saving three kicks to ensure his team edged through 3-2.
John Glyn Roberts
Arwyn Williams
Dion Parry
Tal Huws
Kyle Jones
Peter Twigg
Macauley Lewis
Hugh Alan Jones
Dion Jones
Dylan Griffith
Nathan Sinnott
SUBS USED
Mark Hughes
Josh Clark
Connor Hughes
Jordan Taylor (c)
Joe Caven
Richard Williams
Casey Boylan
Ryan Heywood
Alfie Dodds
Jenson Rowlands
Chris Jones
Cian Owen
Rhys Thomas
SUBS USED
Jack Cowhig
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