It just so happens that the most synergistic cards for Tergrid are also the most unfun
Galvanic Iteration Galvanic Iteration allows you to copy other instants and sorceries for cheap, for 2 mana first and 3 later
Getting some card quality on top of enabling your graveyard synergies without losing any cards total is a big win
Enchantment Color tag templates(None) Thopter Spy Network At the beginning of your upkeep, if you control an artifact, create a 1/1 colorless Thopter artifact creature token with flying
Although, I would still personally play Card not found
For example, if I like making a deck that works by making my opponent discard cards so that he doesnt have anything to use against me, I could make a deck that contains a lot of spells that force him to discard cards. If I want to take that a step further, I could play a card that says whenever a player discards a card, this card does 2 damage to him to make my deck even more efficient