Growth doubles the overall size of the target. The subject gains +1 Size for each 2 Power Points invested when the spell is cast. Each step of Size grants the target a one-step increase to Strength and a point of Toughness. This spell may be cast multiple times on the same target, though the caster must track each casting separately.

Shrink reduces the Size of the subject by one step for each 2 Power Points, down to a minimum of Size -2 (approximately the size of a rat). Each level of Size reduction reduces the target's Strength by one die type (minimum of d4) and his Toughness by 1 (minimum of 2).

Subjects from Size +4 to +7 have the Large ability and fill a 2” square on the table-top. From Size +8 to +10, they are Huge and occupy an area 3” square. If the target is +11 or more, he is considered Gargantuan and occupies a 4” square area. Creatures of Size –2 have the Small ability.¹⁾

For unwilling targets, the caster's arcane skill roll is opposed by their Spirit.

Savage Worlds Deluxe Edition p. 132