First, you can discard any other Machina monster to summon either from the hand, giving you an easy way to get it on the board (and your Citadel to the GY)
Honorable Mentions Multicolored Oko is inexpensive, easily comes down on Turn 2 with a mana creature, and does some strong stuff
Mariposa Military Base A legendary land from the Minas Tirith Magic: The Gathering set The Lord of the Rings: Tales of Middle-earth
If you liked the ideas of the Gadgets but didnt want to pair that with the Machina, might I suggest taking a look at building other Gadget variants such as Gadget-Cubics or Gadget-Kaiju they each build upon old ideas of how to best use the Gadget monsters, bringing them into the modern era with a bit of love
Weakness: Psychic (x2) Resistance: none Retreat: 2 Machamp - Fighting - HP160 Stage 2 - Evolves from Machoke Ability: Strikes Back If this Pokemon is your Active Pokemon and is damaged by an opponent's attack, place 3 damage counters on the attacking Pokemon
A couple of juicy targets include Nyxbloom Ancient for literally all the mana, Inferno Titan to burn away opposing boards, or Craterhoof Behemoth to trample the pod into dust