In this set, mixing and matching abilities on your commander and finding those niche combos among the giant set of cards is fun
Knowing what you are trying to avoid and why is as useful as knowing what you are looking for in a card
One card in each pair of meld cards has an ability that instructs you to exile the two cards and meld them
It fits in the exact same decks as Retribution of the Meek, and yes Dusk costs 1 more mana and doesn't kill regenerating creatures, but you also get Dawn, which is a HUGE bonus for Weenie decks
Mix the mortar with holy wards, or blood will run in the streets. Vadvar, Thraben stonewright Illustrated by John Stanko Standard Not Legal Alchemy Not Legal Pioneer Not Legal Historic Not Legal Modern Legal Brawl Not Legal Legacy Legal Comp
The other question is if it is good enough to see play elsewhere, maybe more as a Think Twice variant