Hagra Crocodile

This is what landfall looks like when the goal is to teach the mechanic rather than break it. The 3/1 that can't block reads as a pure beater, and the trigger that swells it to a 5/3 each time a land enters is the most legible possible demonstration of "play a land, get a benefit": no counters, no permanence, just a combat pump that resets at end of turn. The math is deliberately modest. Four mana for a 3/1 is below rate, and the landfall bonus only redeems it on a turn where you also have another land to deploy, ideally turning an attack into a swing two sizes bigger. That makes the card a deckbuilding signal more than a threat: it wants a high land count, it wants extra-land effects, and it punishes a draw that stumbles on its mana. The "can't block" clause is the flavor tax on a creature whose whole identity is forward motion; the crocodile is built to keep advancing while you keep dropping lands, never to hold the fort, and the restriction keeps it honest to that role rather than letting it double as a defensive body. It belongs to the first wave of landfall creatures designed to make a now-staple mechanic immediately readable to anyone opening a pack, and its ceiling is exactly as high as the number of lands you can still get into play.