"Dark Master - Zorc" is often overlooked due to the negative effect of rolling a six. However, "Zorc" is similar to "Snipe Hunter" in many respects and can be extremely powerful when paired with proper support to mitigate the risk.
Use "That Six" to ensure that only the opponent's cards get destroyed; If the roll is a 2, 4, or 6, "That Six" can change it to a 1, whereas if a 1, 3, or 5 is rolled, you can let the roll stand, and a 2 can go either way (being changed to a 1 would not change the outcome). As such, rolling a 1, 2, 4, or 6 will destroy all of your opponent's monsters, while a 3 or 5 will destroy one, but no outcome would destroy your own field.
Combine this card with "Ritual Cage" so that "Dark Master - Zorc" won't be destroyed by his own effect if his dice roll lands on 6.