Cubes built around themes like snow, or loaded with artifact or enchantment creatures, will get a lot of mileage from Embiggen
The card can be drawn if the power of the Forward becomes 0, and as per the rule they are then put in the Break Zone
While piloting the Golgari Yawgmoth deck, Ive regularly ruined an opponents board simply by killing off their creatures/shrinking them enough to make attacking unprofitable, and Ive even proliferated an opponents Chalice of the Void from one to two to lock them out of casting a bunch of spells
Last week it shot from $4 to $8 within a few days, and its value is currently at $9.20
Combine it with cards like Life and Limb, Sporoloth Ancient, or anything that lets you play more lands per turn for maximum value
So, the Mask is a combo with a lot of cheap creatures that have ETB restrictions, like Phyrexian Dreadnought or Lord of Tresserhorn