My longest was a 4 hour 4v4 on my ice. (I flee at 4 hours, usually) my shortest (that i remember) was a tournament match that was under a minute on my balance. I am warlord, at about 1400 rating on him. I was battling a level 27 private lol.
My longest duel: there was a lot of passing and my enemy, she was just passing and placing a lot of healing spells (not sure how long it took me, but it was pretty long). My shortest duel: i was fighting with this guy and i gave him a chance to destroy me, but he gave me another chance to destroy him (consider it 5 seconds short).
4-5 hours against a life wizard with Guardian Spirit. I killed him 5 times before I was finally able to kill him before he got another guardian spirit up. This is the reason I have once again retired from PvP.
If Reshuffle was demoted to treasure card status because KI thinks it made for long matches, then Guardian Spirit absolutely needs to be demoted to treasure card status, if KI has any interest in being consistent with their logic.
i can't decide on the long one because one time me and my friend gavin nighthand did a battle when we only used ranked 1-6 spells with no blades or trap help only minions and bubbles no shields no weaknesses and it lasted for like 2 hours and he went first and since he kept summoning minion it made it harder to kill him since he summoned it like 3 rounds after i killed his talos (he was using his myth and i was using my death we're both promethean) and he kept healing it which made it even harder. and he used enchantments and i had none and since he had an attack bubble that helped him with his attacks he was easily able to kill my death minion no matter how powerful it was XD and then he had to go to store and i had to shower and he let me kill his minion before we left since we were gonna be afk and then after we came back we both healed and then like after like 2 hours he finally had me down at low health and then killed me before i could heal and another time i wanted to duel my life friend john wanted to duel (he has a life wizard and he's an adult) i use a life mastery on my death but i am planning on making a new death with a balance mastery then i used sanctuary and he kept using guardian spirit rofl and he kept spamming shields which made it hard for me to kill him then after i shattered he shielded again rofl XD then after i killed him like 5 times he still came back then i ran out of shatters then we agreed that with the spells in our decks neither of us is gonna win so we decided to call it a draw and pvp together since it was such an intense duel we decided to combine our strength. and my shortest duel was in a practice duel against a storm she kept spamming wild bolt and was hitting 789 and i had a valcanic shield on then she easily killed me and then a second time she beat me again and was being rude saying i needed "juju" for my strategy i nearly reported her but i knew it would just be useless. and i apologize that my comment was so long (Blaze ravenmender level 59 Blaze moonmender promethean)