You could tell by looking at them that the two duelists were not beginners and were taking their battle far too seriously to waste time cracking jokes....
Jon led off the duel by playing [1], and had nothing further for his turn. Kai responded by playing [2] on his turn and passed.
In his second turn, Jon played [3] and tapped out to cast [4]. Jon tried to end his turn but Kai cast [5] in his end step. Jon discarded [6], the best fatty ever printed, with just a hint of a smile. On his turn, Kai responded by playing [7] and tapping out to produce two mana to cast [8]. Having nothing further, he let Jon go again.
Jon began by attacking with [4], which [8] could not block because of [4]'s protection ability. Jon then put [9] into play. He tapped [1] to activate [9] and tapped [3] to cast [10] with three +1/+1 counters. Contemplating using [11] during his attack, Kai played [12]. Then he attacked with [8]. Jon sensed a trick and let it through. Indeed, [11] would have let Kai kill [10] and get damage through anyway. Kai then tapped out, taking a point of damage, and since he had done damage this turn he was able to cast [13] without having to sacrifice it. Then he let Jon go.
Jon attacked with both his creatures, and Kai still couldn't profitably block. Jon cast [14] face down and put [15] into play tapped. On Kai's fourth turn, he just cast the [16] he just drew and held back his creatures.
Jon untapped, drew his card and thought for a bit, eventually deciding to attack with [4] and [10]. Kai was ready, quickly blocking [10] with [8] and [4] with [13]. [4] got +1/+1 when blocked, but that was not going to be nearly enough. Kai tapped [12] (taking another point) and [7] to cast the [11] he'd represented targeting [8]. Now [8] was easily big enough to kill [10] and survive. Then, he tapped [2] and [16] and sacced [7] to cast [17] targeting Jon. It resolved and [13] got five +1/+1 counters. Jon could only let both his creatures die while Kai's lived. After combat though, he cast [18] at [13] to finish it off (tapping [1] and [3]). Kai let out a sigh but even if he had held [11] back to protect [13], [18] would still have done just enough damage. [19] came into play tapped, and it was Kai's turn. Kai played [20] and cast [21] (tapping all his lands, taking another point) to destroy [1], hoping that shutting down [3]'s ability to produce colored mana, especially reusable red mana, would cause Jon problems . [1] also happened to be the only target in either deck that would let Kai gain a life upon resolution of that spell. [8] attacked for the second time and then Kai passed the turn.
Seeing no blockers, Jon attacked with [14]. Kai tapped [16] and cast [22] destroying it. If Jon had had a white source other than [15] he would have been able to flip [14] over and save it. Kai was relieved to have dealt with the potential flyer before it started causing trouble. Jon decided to just play [23] tapped and be done. On Kai's turn he just attacked for two with [8] again and was done.
Jon drew for his turn. Looking to shake things up, he cast the [24] he topdecked by saccing [15] and using one of the mana to activate [9]. Jon discarded [25], and frowned when he saw Kai discard [26]. Both players drew up to seven and Kai tapped [2], [16], and [20] to cast [26]. Jon played [27] and passed the turn. Kai attacked with both his creatures. Jon tapped [19], [3], and [27] (taking a point) to cast [28] targeting [26]. It resolved, killing [26] and letting Jon draw a card. [8] got through unmolested though. After combat, Kai played [29] and tapped [2] and [12](taking a point) to cast [30].
On Jon's next turn, he put [31] into play tapped. He quickly counted the cards in his graveyard and then he tapped [19] to activate [9], and tapped [3] and [23] to cast [32] threatening to kill all of Kai's creatures. Kai also looked over his graveyard, and then he tapped [29] and [16] to cast [33] targeting [8] removing [13] and [26] from the game. In response to his own spell, he activated [20] targeting [30]. When the dust settled [33] destroyed [8] (which was destined to die anyway), but [32] was now a point shy of sending [30] to the graveyard. Kai sent [30] to attack unhindered next turn. Then he played [34] and tapped it, [12] (for colorless), [16], and [20] to cast [35] at Jon. It would have been just enough damage to kill him, but Jon was able to cast [36] pitching [37] to counter it, taking a point but staying alive.
Jon untapped and tapped [23] to activate [9]. He used one of the mana to cast [38] targeting himself to draw three cards. Jon was now able to remove the immediate threat. Using the other mana in his pool Jon sacced [27] targeting [30]. Then he cast [39] at [30] by tapping [31] and [3]. He even gained 2 life in the process. Jon then played [40] tapped and was done. Kai played [41] and tapped it to cast [42], and tapped [2], [12] (hurting himself yet again), [16], and [29] to cast [43]. If either got through unblocked it would be just enough to finish Jon with the help of [29]. To further cut Jon's options, Kai sacced [34] to destroy [23], eliminating a blocker that could have gotten in the way of [42] even if it used its evasion ability.
But Jon still had answers. He untapped and played [44]. He then tapped [40] (removing a counter) and activated [9] to cast [45] (leaving one mana floating), and then tapped [3], [19], and [31] to cast [46]. Immediately upon [46]'s resolution, 420.5e triggered sending [46] and [43] to the graveyard. On Kai's next turn he went for the win again. He tapped [2] to use [42]'s ability, leaving [45] unable to block it. Once that resolved, [42] attacked, and Kai tried to activate [20] targeting [42] after blockers. After that, Kai had been planning to tap [2] and [12] to use [29] also targeting [42]. In response to the activation of [20], Jon tapped [44] to cast [47] targeting [42] though. Thus, [42] was destroyed before the resolution of [20]'s ability made [47]'s drawback lethal. All Kai could do instead was tap [12] (another point) to cast a wall, [48], which was looking rather useless.
And on the next turn, Jon finally peeled the [49] off the top of his deck that he'd been waiting for. He tapped [40], causing him to sacrifice it, and activated [9] to cast [49] enchanting the long-forgotten [6], bringing it into play. He played [50], a dual land, and tapped it and used the other mana that was floating in his pool to cast [51] to return [37] to his hand. [45] then attacked and got through since it had protection from [48]'s color. The game slipping from his hands, Kai tried to cast [52] tapping [2] and [29]. If it resolved it would have done 10 damage to Jon and 8 to Kai. Jon was not about to take the draw though. Instead, he tapped [19], sacrificing it, and tapped [31] and [3] to cast [37], which countered [52]. That was all Kai could do, and the end was near.
On his turn, Jon tapped four lands ([3] activating [9], [50], and [31]) to cast [53] enchanting [2]. He then attacked with all five of his creatures. Even blocking optimally, Kai took just enough damage to die.