Whenever Lorthos attacks, you may pay . If you do, tap up to eight target permanents. Those permanents don't untap during their controllers' next untap steps.
Cast a giant 8/8 octopus, then either beat down or use his attack trigger to lock down everyone's blockers, lands, and threats. You ramp hard into Lorthos, protect him, and turn his repeated tap-down into a soft Stax lock while your evasive/big creatures close the game. He's a mono-blue beater that doubles as a board-controlling Kraken commander.
Huge 8/8 body that demands removal and pressures any board
Repeatable tap-down of up to 8 permanents creates a soft lock on opponents
Mono-blue gives access to the best counters, card draw, and protection in the format
Synergizes naturally with sea monster/big-blue tribal payoffs
Eight mana to cast plus eight more to use his trigger is brutally expensive
Single-color means no access to wipes, ramp creatures, or efficient removal outside blue
Dies to any spot removal, restarting the whole investment
Tap effects don't kill anything, so you still need real win conditions
Shrouded, trample, islandwalk beater that pairs with Lorthos's lockdown for unblockable damage.
Lean into mono-blue ramp—Sol Ring, Mana Vault, High Tide, and Caged Sun—so you can cast Lorthos and activate his trigger the same turn. Add unblockable enablers (Whispersilk Cloak, Aqueous Form, Thassa) and protection (Swiftfoot Boots, counterspells) so your investment sticks. For a real ceiling, slot in fast wins like Quietus Spike, Stroke of Genius/Blue Sun's Zenith finishers, and untap engines (Seedborn Muse, Thousand-Year Storm) to make tap triggers oppressive.