Suggested by Sonic Beelzemon is a really powerful Digimon. Serpent’s defenses should protect him against the energy guns for quite a while but once Beelzemon activates his chaos mode then it’s all over. His attack power skyrockets and would just be too much for Serpent to try and defend against. The unrelenting attacks would really take their toll. Beelzemon also has the speed advantage here which really puts the ball in his court since he can dictate the terms of battle on if this is close or long range. Beelzemon wins.