[AUTO](VC):When this unit attacks, if the number of cards in your opponent's damage zone is three or more, this unit gets [Power]+2000 until end of that battle.
[CONT](VC/RC): Lord (If you have a unit that doesn't belong to the same clan as this unit, this unit cannot attack)
Basically, Eraser allows you to perform an explosive follow-up at the cost of 1 card (the card used to ride the grade 3, kinda like a persona blast), giving you a massive boost of power, as well as an ability to retire a unit in the front row, preferably retiring a power unit (Palomedes, 12k units etc) or in most cases, an intercept unit.Even when using A copy of itself to ride on Eraser, its a 1-for-1 card exchange while retaining an effect similar to Dragonic Waterfowl's, as well as maintaining that Limit Break ability to be used on the following turn.
This snowballs the advantage gained when used with units with "On-Ride" skills like ThunderBreak Dragon and Voltage Claw Dragon, retiring 2 units at the cost of CB2 while gaining a massive power boost of 10000. 25000 power VG at a cost of 1 card feels nice.
Here's a deck that I've been using on BYOND:
4 Eraser, Vowing Sword Dragon
4 Divine Seal Dragon Dungaree
4 Dragonic Deathscythe
4 Demonic Dragon Berserker, Garuda
3 Thunderstorm Dragoon
4 Red River Dragoon
4 Desert Gunner Raien
4 Wyvern Guard Garudo
2 Photon Shot Wyvern
8 Crit 4 Draw 4 Heal
SV: Spark Kid Dragoon
Might reduce the number of copies of Dungaree for more reliable rear-guards like Djinn of the Lightning Flash. Other than that, it's very aggresive, with the retire and power boosts.