Combos with Moat

1. All creatures your opponent control lose flying.
2. Moat prevents things without flying from attacking.
3. Creatures your opponent can not fulfill the conditions necessary to attack.

Because Sandwurm Convergence prevents creatures with flying from attacking you, and Moat prevents creatures without flying from attacking you, no creatures can attack you.

1. All creatures lose flying and Islandwalk.
2. Moat prevents things without flying from attacking.
3. Creatures can not fulfill the conditions nessasary to attack.

1. Gravity Sphere causes all creatures to lose flying.
2. Moat prevents non-flying creatures from attacking, and since no creatures can have flying, no creatures can attack.