Snake (SSBB)/Down tilt
Snake sweeps his leg across the ground while in a crawling position. The move deals 10% and high vertical knockback, with the move's power varying depending on where Snake's leg connects. The move KOes Mario on Final Destination at 133% at the foot, 140% if the opponent is very close and at 121% at the middle of Snake's leg. The move comes out fairly fast on frame 6 and the move has a good amount of horizontal range, with the move having a disjoint (albeit to a lesser extent than Snake's other tilts although its lateral horizontal range is similar to forward tilt). Snake also stays quite low to the ground which can allow him to avoid various attacks while using the move. All these factors combined make down tilt a solid KO option at higher percents, especially when his other KO options are stale. Repeatedly using down tilt additionally causes Snake to move slightly forward with each down tilt.
Down tilt does have fairly high ending lag however, with the move having 34 total frames. This makes down tilt fairly punishable when it does not hit as well as preventing Snake from having any followups out of the move when it connects although the move does have high knockback at lower percents, making it safe on hit. The biggest detriment to down tilt however is the fact that it is possessed by Snake, whose other tilts outclass it. Forward tilt comes out faster, it can deal a lot more damage, it can KO earlier depending on the opponent's stage position and it is more disjointed. Up tilt comes out just as quickly as down tilt, it is much stronger, it is more disjointed and it can hit opponents above Snake. This heavily limits down tilt's use as in most situations where down tilt can be useful, Snake is usually better off using one of his other tilts. The only advantage down tilt has over Snake's other two tilts is that Snake low profiles while using it but even then, Snake low profiles less than when he is simply crouching or crawling.
Overall, Snake's down tilt is a solid move due to its good speed, range and power although it is easily the least effective tilt Snake possesses. The move is fairly solid on paper but due to how incredible Snake's other tilts are, down tilt is not a highly useful move overall.