Meta Knight (SSB4)/Down aerial
Meta Knight does a quick slash beneath him. This move is similar to his up aerial in both appearance and function. It has the least startup of any down aerial, as well as decent range. The sweetspot of the slash is also a semi-spike, making it deadly offstage, and is relatively easy to land, as it takes priority over the sourspot, providing Meta Knight with a very quick and effective edge-guarding tool.
The move's speed makes it an effective out of shield option, and it grants Meta Knight a useful combo-breaker and great defense against juggles. It can be used to pressure grounded opponents and cover Meta Knight's aerial approach. However, it is unsafe to use close to the ground, as it has high landing lag, the highest of all his aerials.