The team composition is as follows from right to left:

Troll with Graduation Cap - Damages Wind Face to spawn clouds

Wind Face with Bandage - Spawns a cloud when damaged. The bandage allows the Wind Face to never be destroyed from the Troll as it heals for 1 damage when it takes the 1 damage from Troll.

Saluting with Graduation Cap - Gains attack from destroyed allies.

Witch with Handshake - Gives summoned units its attack. Handshake allows the witch to gain 50% of the attack Saluting gains.

Shark with Handshake - When an ally is summoned, destroys it and gains x% of its stats. Handshake allows the Shark to gain 50% of the witch's attack.

How the build breaks the game (reaches e247 damage):

The Troll damages Wind Face, summoning a cloud. The cloud gets damage from the Witch, the Shark destroys the cloud and gains stats, and the Saluting gains attack from the destroyed cloud, which gives 50% of its attack gained to the Witch, increasing the amount of damage that the Witch will give to the next cloud, which then increases the amount of attack the Saluting and Shark will gain from the next cloud being destroyed. This buff loop starts raising the Shark, Saluting, and Witch's damage exponentially and will eventually get the Shark to e247 damage and crash the game.

How to achieve this yourself:

Leveling all members of the team is beneficial, but the most beneficial would be the Troll, Saluting, and Witch. Leveling the troll allows for more "Buff Loops" to occur before attacking again. Leveling the Saluting and Witch are important for raising the damage number exponentially as the Saluting gains the attack with its ability and the Witch raises the attack of the next cloud with the attack that was given from Handshake. The Wind Face is really only there to spawn clouds, as the HP of the clouds does not matter because the game should crash anyways. The Shark is only there to destroy the clouds to activate the Saluting's ability. The Shark is the first one to reach e247 damage because it is the last one to act in the "Buff Loop".

Leveling up team members does require some luck, but using a FAX Machine Relic along with Graduation Cap Runes is a great way to start an EXP Farm. If the FAX Machine copies a card it keeps the rune, giving you multiple of the same card with Graduation Caps which provides passive EXP between rounds. By round 25, you can easily level up a team member a few times. Golden cards copied give 2x EXP when merged. With a graduation cap this is an easy 2 EXP gained per round!

Getting the right Golden Cards is quite rare. There is a slight tip around this that could help you out. The Link Rune. If you find any golden card, you can attach the Link Rune to it and then combine it with the card that you want to make golden.

Although Golden cards help out quite a bit, I think the only card you should prioritize getting golden is the Troll, as having it golden makes it attack the ally behind 2x as much, doubling the amount of "Buff Loops" and therefore exponentially increasing the speed at which e247 damage is reached.

This Guide was written as of Version 1.0.2c