When they tell you "controller strongly recommended", they mean it: game is utter garbage with a kb/m. Not just "bad control scheme", I mean straight up "the mouse is treated as a joystick with absolute ♥♥♥♥ acceleration and you will find it impossible to move across the screen without constantly lifting and dragging".
Also unless you plan to have people over to play this it's kind of limited in fun quotient. AI is not amazing, and it seems a lot like this would benefit from ♥♥♥♥ing around with pals. But the multiplayer is local-only.
Go buy Go Home Dinosaurs instead from the same company, it's just a much better GAME if you can deal with some clever tower defense puzzles instead of... uh... defending literal towers of blocks.