Karmautility$32.56A classic black-hate enchantment with a similarly global, board-warping continuous effect. It also changes how the table functions each turn, though in a different axis.
Painter's Servantutility$67.46It globally changes the color of permanents and cards, similar to Darkest Hour's universal color modification. It is more flexible and asymmetrical in practice because it affects all colors chosen.
ConspiracyutilityBudget$0.44Like Darkest Hour, it applies a sweeping color/subtype-changing effect to your creatures. It is much more expensive, but it serves a similar deck-building role in tribal and combo shells.
Living Planeutility$184.42Another cheap enchantment that dramatically alters the characteristics of creatures or lands globally. It is a different transformation, but it fills the same 'rule-changing enchantment' role.
Blanket of NightutilityBudget$0.98It globally changes lands into Swamps, which is a similar kind of continuous color/land-type manipulation. Like Darkest Hour, it enables color-reliant synergies by rewriting game objects.
Fervorutility$4.30A low-cost global enchantment that provides a simple but impactful continuous team-wide effect. While it changes combat rather than color, it occupies a similar cheap enchantment support slot.
Arcane Adaptationutility$3.49It gives your chosen creature type to your creatures and libraries, functioning as a modern tribal enabler. It is the closest structural analogue to a one-mana global rules-changing enchantment.
XenograftutilityBudget$0.62It globally changes your creatures' creature type, which is comparable to Darkest Hour's blanket characteristic-changing effect. It is more expensive but often used in similar combo and tribal setups.