Green-based Tron decks are the scourge of many Modern players' tournaments. turn three Karn Liberated is an absolute nightmare for many decks in Modern, and is one of the most powerful things you can be doing. That said, it's not the only thing that you can do with your Tron lands in Modern. There have traditionally been any number of Blue decks that have leveraged cards like Urza's Tower and Cloudpost to do some really busted things, and Modern is no different:

Mono-Blue Tron | Modern | h0lydiver, 5-0 Competitive Modern Constructed League

• Creatures (7)
• 1 Snapcaster Mage
• 1 Torrential Gearhulk
• 1 Walking Ballista
• 2 Treasure Mage
• 2 Wurmcoil Engine

• Planeswalkers (2)
• 2 Ugin, the Spirit Dragon

• Instants (18)
• 1 Cyclonic Rift
• 2 Repeal
• 2 Spatial Contortion
• 2 Supreme Will
• 3 Remand
• 4 Condescend
• 4 Thirst for Knowledge

• Artifacts (9)
• 1 Batterskull
• 1 Mindslaver
• 1 Oblivion Stone
• 2 Chalice of the Void
• 4 Expedition Map

• Lands (24)
• 8 Island
• 1 Academy Ruins
• 1 Gemstone Caverns
• 2 Field of Ruin
• 4 Urza's Mine
• 4 Urza's Power Plant
• 4 Urza's Tower

• Sideboard (15)
• 2 Chalice of the Void
• 2 Dismember
• 1 Gemstone Caverns
• 2 Grafdigger's Cage
• 2 Hurkyl's Recall
• 1 Mindslaver
• 1 Negate
• 1 Spatial Contortion
• 2 Summary Dismissal
• 1 Wurmcoil Engine

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Instead of filling your deck with baubles and cantrips, you get to play cards like Condescend and Remand to help stall your opponent out while you build up your mana and dig for Tron. Instead of Ancient Stirrings helping you do something broken quickly, you have Thirst for Knowledge which still helps find the cards you need, but also generates card advantage over a longer game. You lose most of the explosive potential of casting early Karns and World Breakers, but in exchange you gain access to powerful Blue cards like Cyclonic Rift and lategame engines like Mindslaver and Academy Ruins.

If you're looking for a big mana control deck that combines some of the explosive potential of Tron decks with the overbearing late game of control, this seems like a very reasonable choice. You don't have access to some of the same traditional control haymakers like Jace, the Mind Sculptor and Cryptic Command, but instead you have the ability to overpower your opponents with a ton of mana, and potentially lock them out of the game with cards like Ugin, the Spirit Dragon, Mindslaver, or even Spell Burst.