Some in-depth information on Down-Tilt:
D-Tilt doesn't have fixed knockback, so its frame advantage is affected by Rage and the victim's percents. Higher knockback pushes people away further (duh), but because its knockback is so small until you get to 150+%, it doesn't put people into tumble, which means it cannot be DI'd.
On shield, D-Tilt gives -11 frame advantage, but your hand is not a grabbable hurtbox, so we're working with something like Meta Knight/Pikachu D-Tilt in terms of general safety here, as it takes seven frames to drop a shield normally. You're vulnerable to some Up-Bs out of shield if not well-spaced, though, because your hand is still hittable.
Wario's D-Tilt has two hitboxes: One at the glove that sends opponents at a 46-degree angle and one at the finger that sends opponents at a 67-degree angle. Same power and knockback, but the glove hitbox has priority over the finger one. The following numbers all assume 0% Rage with a fresh D-Tilt with the close hitbox. and they're pretty dependent on weight and fall speed (fall speed can sometimes mean we don't get the couple frames of landing lag to exploit). Generally speaking, the lower those are, the better frame advantage we have.
At +5, D-Tilt -> D-Tilt, D-Tilt -> Dash Attack, and D-Tilt into Half Waft are true combos. The last one has to be right on top of the opponent or a run turnaround D-Tilt.
At +8, D-Tilt -> Jab, D-Tilt -> Dash Grab, and D-Tilt -> D-Smash are true combos. The last one has to be right on top of the opponent or a run turnaround D-Tilt.
Some characters who are hit by D-Tilt can buffer a command before they touch the ground. Because you can only buffer one command at a time, and buffer priority is Special > Shield > Attack > Jump, opponents attempting to Shield, Grab, or Roll will buffer an airdodge, giving you 20 more frames of vulnerability than normal (compared to the two extra from landing lag). Have you ever landed D-Tilt -> F-Smash before? It's likely because of this. Only a handful of characters have this property at any range, but many more have it from a D-Tilt that hits at the tip. Here's a list that shows what characters it works on:
Any range: Jigglypuff, Kirby, Olimar, Peach, Rosalina
Tip only: Bowser Jr. (100+%), Dark Pit, Donkey Kong (very specific distance; not recommended), Dr. Mario, Duck Hunt, Little Mac, Lucario, Lucina, Luigi, Mario, Marth, Mewtwo, Mii Gunner (small), Mr. Game and Watch, Ness, Pac-Man, Pit, Robin (65+%), Samus, Shulk (non-Jump), Sonic (75+%), Toon Link, Villager, Wario (95+%), Wii Fit Trainer (54+%), Yoshi, Zelda
Doesn't work: Bowser, Captain Falcon, Charizard, Diddy Kong, Falco, Fox, Ganondorf, Greninja, Ike, King Dedede, Link, Mega Man, Meta Knight, Mii Swordsman (small), Palutena, Pikachu, R.O.B., Sheik, Shulk (Jump), Zero Suit Samus
Yellow numbers denote 50% Rage,
Orange numbers signify 100% Rage, and
Red numbers represent 150% Rage.
Character | +5 Frame Advantage | +8 Frame Advantage | Can buffer up close? | Can buffer at tip?
Mario | 48%,
44%
,
33%
,
23%
| 88% | No | Yes
Luigi | 29%,
26%
,
16%
,
8%
| 65% | No | Yes
Peach | 20% | 53% | Yes | Yes
Bowser | 60% | 110% | No | No
Yoshi | 39%,
35%
,
24%
,
15%
| 79% | No | Yes
Rosalina and Luma | 9%,
6%
,
0%
,
0%
| 38% | Yes | Yes
Bowser Jr. | 60% | 101% | No | Yes at 100+%
Wario | 59% | 100% | No | Yes at 95+%
Donkey Kong | 37% | 82% | No | No
Diddy Kong | 59%,
53%
,
43%
,
32%
| 93% | No | No
Mr. Game and Watch | 33% | 67% | No | Yes
Little Mac | 35% | 70% | No | Yes
Link | 50% | 94% | No | No
Zelda | 22% | 55% | No | Yes
Sheik | 54%,
51%
,
41%
,
30%
| 88% | No | No
Ganondorf | 65% | 102% | No | No
Toon Link | 36% | 66% | No | Yes
Samus | 32% | 71% | No | Yes
Zero Suit Samus | 55%,
50%
,
39%
,
30%
| 87% | No | No
Pit | 26% | 65% | No | Yes
Palutena | 58% | 92% | No | No
Marth | 29% | 64% | No | Yes
Ike | 59% | 100% | No | No
Robin | 51% | 92% | No | Yes at 65+%
Duck Hunt | 31% | 66% | No | Yes
Kirby | 12% | 41% | Yes | Yes
King Dedede | 26% | 71% | No | No
Meta Knight | 54% | 86% | No | No
Fox | 54% | 86% | No | No
Falco | 55% | 87% | No | No
Pikachu | 54%,
49%
,
39%
,
29%
| 86% | No | No
Charizard | 66% | 104% | No | No
Lucario | 44% | 84% | No | Yes
Jigglypuff | 0%,
0%
,
0%
,
0%
| 22% | Yes | Yes
Greninja | 59% | 93% | No | No
R.O.B. | 56% | 99% | No | No
Ness | 33%,
29%
,
19%
,
10%
| 69% | No | Yes
Captain Falcon | 62%,
57%
,
45%
,
34%
| 98% | No | No
Villager | 35% | 72% | No | Yes
Olimar/Alph | 17% | 49% | Yes | Yes
Wii Fit Trainer | 53% | 91% | No | Yes at 54+%
Shulk (non-Jump) | 47% | 87% | No | Yes
Shulk (Jump) | 61% | 97% | No | No
Dr. Mario | 48% | 88% | No | Yes
Dark Pit | 26% | 65% | No | Yes
Lucina | 29% | 64% | No | Yes
Pac-Man | 25% | 60% | No | Yes
Mega Man | 61% | 94% | No | No
Sonic | 52%,
48%
,
37%
,
26%
| 93% | No | Yes at 75+%
Mewtwo | 24% | 58% | No | Yes
Mii Gunner (small) | 36% | 77% | No | Yes
Mii Swordsman (small) | 48% | 92% | No | No
Mii Brawler (small) | | | |