By using the Tea's Holy Guard skill, you can use the effect of a Yomi Ship actively. During you turn, get a Yomi Ship to attack an attack position monster that has higher attack than that of it. The Yomi Ship is destroyed in a battle, and the monster that defeats the Yomi Ship is also destroyed. You do not receive battle damage for the effect of Holy Guard skill.
How to get
[Holy Guard] You receive no battle damage during your turn.
This card is basically outclassed by Exploder Dragon now, so why should it be banned and that card is okay?
Even more underrated as it seems, this card is a great econ bait and even a mirror wall counter! If your opponent has only one monster on the field and you can special summon this with Hammer shark, you can attack with yomi ship for either a guaranteed kill or a wasted windstorm/econ/risk-free mirror wall.