In recent years, the tower rush genre has seen an explosion of creativity, fundamentally altering how matches are played.

We have moved far beyond the simple days of dropping a heavy tank at the bridge and hoping it connects with the tower.
Controllable Units
For a small elixir cost, you can now force your Champion to dash, turn invisible, or summon a massive protective shield exactly when you need it.

It shifted the focus slightly away from pure macro-level resource management and heavily toward micro-level unit control.
A Champion without its ability is just an overpriced, mediocre unit.If you dash before they drop their swarm, you waste the skill.Protect them. Evolving the Meta
Another massive recent innovation is the concept of 'Card Evolutions', where standard units gain new powers after being played multiple times.

You must know exactly when the opponent is holding an Evolved unit, as treating it like the standard version will result in a lost tower.
Innovative FeatureHow it WorksPower SpikesPlay a specific card X number of times to unlock a supercharged version for the next deploymentTower TroopsPlayers can now swap the default Princess on the tower with different characters that shoot faster, slower, or deal splash damage What Will They Think of Next?
While controversial among some purists, these changes are absolutely vital for maintaining a massive, engaged player base.

Innovation is the true king of the arena.