Untimely Malfunction fits the bill
Rangers of Ithilien would be another card you could add to increase your thievery skills while you could also look into going postal on the amass theme, adding Zombies with Dreadhorde Invasion and then stacking the deck with other amass cards
Some creatures like Reflector Mage and Ghalta have strong enter the battlefield effects that can change the game
While not abundant, reds graveyard hate cards can provide crucial disruption in specific matchups
Every dual land comes with a cost or trade-off: Life payments Shock Lands cost 2 life, Pain Lands cost 1 life per colored mana Tempo loss Tapped entries delay plays by one turn Deck construction requirements Check Lands need typed lands, Tango Lands need basics Conditional reliability Fast Lands fail late game, Battlebond Lands fail in 1v1 To choose the right balance, make sure to consider the format, deck speed, and overall strategy
I truly recommend you give Arena Tutor a try if you want more detailed insights into the stats for each of your decks