More Than Meets the Eye (You may cast this card converted for .)
Your opponents can't cast spells during combat.
At the beginning of each of your postcombat main phases, you may convert Megatron. If you do, add for each 1 life your opponents have lost this turn.
Living metal (During your turn, this Vehicle is also a creature.)
Whenever Megatron attacks, you may sacrifice another artifact. When you do, Megatron deals damage equal to the sacrificed artifact's mana value to target creature. If excess damage would be dealt to that creature this way, instead that damage is dealt to that creature's controller and you convert Megatron.
Megatron is a Mardu artifacts/damage deck that punishes opponents for losing life. Lock combat down with the tyrant side's spell restriction, then attack, sacrifice artifacts to ping creatures and bleed players, and on your postcombat main phase convert to Destructive Force to generate massive colorless mana off all the life lost this turn. Funnel that ramp into big payoffs while grinding the table down with incremental damage and recursion.
Built-in combat protection: opponents can't cast spells during combat, blanking many removal and combat tricks while you attack
Generates explosive colorless mana on your second main phase when opponents have hemorrhaged life
Flexible damage outlet that turns any artifact into a removal spell or face damage via excess-damage trample-style overflow
Synergizes with the entire artifact/aristocrats toolbox in three colors
As a Vehicle/living-metal commander it dodges sorcery-speed sweepers on your own turn and is hard to keep down
Mana value 6 and color-intensive; without the alternate cast it's slow to deploy
Reliant on having sacrificial artifacts to use the attack trigger meaningfully
Conversion mana is use-it-or-lose-it and only useful if you have big spells to dump it into
Vulnerable to artifact removal and graveyard hate that strip your fodder
Spell-restriction lock is only during combat, so it doesn't stop sorcery-speed answers
Legendary Artifact Creature — Robot // Legendary Artifact — Vehicle
for each 1 life your opponents have lost this turn.