Lignifyremoval$0.63Turns a creature into a harmless 0/4 Treefolk, serving a similar defensive role by neutralizing an attacker without destroying it.
Deep Analysisutility$0.32Not a direct combat trick, but if you're looking for green-style ways to blunt an opposing threat, this is not functionally similar enough to be a true equivalent.
Serrated Arrowsremoval$0.29Can repeatedly shrink creatures over multiple turns, which overlaps with the debuff/weakening role of Shrink in a more persistent way.
Myojin of Life's Webutility$6.40Not similar in function; it is a ramp/creature payoff rather than a temporary power reduction spell.
Dead WeightremovalBudget$0.04A cheap enchantment-based answer that weakens or removes small creatures, functioning as a more permanent combat neutralizer than Shrink.
Enfeeblementremoval$0.15Directly reduces a creature's power for multiple turns via a debuff aura, closely matching the idea of making a creature far less threatening.
Spontaneous MutationremovalBudget$0.03A low-cost way to shrink a creature's combat stats, often making it ineffective in combat much like Shrink does for a turn.
Mortal Woundremoval$0.08Provides a repeatable shrink/neutralization effect by punishing creatures after they deal damage, playing a similar low-cost defensive role.