Usually, most PCs rely solely on their Dexterity ability score modifier for their initiative; however, there are ways to get bonuses to initiative. How high can this bonus get?
For example, there's the Alert feat (PHB, pg. 165):
Always on the lookout for danger, you gain the following benefits:
- You gain a +5 bonus to initiative.
The Dread Ambusher class feature of the ranger Gloom Stalker archetype (XGtE, pg. 42):
At 3rd level, you master the art of the ambush. You can give yourself a bonus to your initiative rolls equal to your Wisdom modifier.
And the Tactical Wit class feature of the wizard War Mage archetype (XGtE, pg. 60):
Starting at 2nd level, your keen ability to assess tactical situations allows you to act quickly in battle. You can give yourself a bonus to your initiative rolls equal to your Intelligence modifier.
So, a level 6 character who was a Ranger 4/Wizard 2 who took the Alert feat at level 4 would have an initiative bonus of 5 + DEX + WIS + INT.
So, if my Ranger 4/Wizard 2 example above made it all the way up to level 20 (Ranger 18/Wizard 2) and used all their ASIs to max out DEX, INT and WIS, they would then have an initiative bonus of 20.
What character build (up to level 20 if necessary) gives the maximum initiative bonus?
Or, is the one I have outlined here the highest you can get?
For the purposes of this, let's assume the PC is a human (+1 to all ability scores) whose player was lucky enough to roll all 17s during character creation; hence the character has +4 in every stat (for convenience). Anything RAW is allowed; multiclassing, feats, magic items, etc, but nothing from Unearthed Arcana. No temporary effects. Things that grant advantage or half-proficiency count, but nothing temporary.
I'm going to disregard any DM sanity here, and assume anything and everything published is on the table and can be mashed together...
Attributes - +10
Class - +33, +43 total
The starting 18s across the board allow for unlimited multi-classing, so we won't have any problems getting the build off the ground before we go hunting for shenanigans. You'll probably want to start with Fighter for the Heavy Armor Proficiency, because there's a solid bonus available only on a suit of Plate.
Feats - +5, +48 total
At some point, one of the classes needs to be taken to L4 to earn an ASI for:
Equipment - +8 minimum, possibly infinite.
Right off the bat we can get +5 from Scorpion Armor2. It would be beneficial to be a Yuan-Ti Pureblood, because Scorpion Armor tries to kill the wearer via poison damage each time they take it off or put it on.
A Stone of Good Luck gives another +1 to all ability checks, while the Ioun Stone of Mastery increases the character's proficiency bonus by 1, which benefits Remarkable Athlete. We can use one or the other, because we've got an attunement slot limit.
While we're talking items, you'll want something like a Sentinel Shield to grant advantage on initiative - the Weapon of Warning or Rod of Alertness are out because we are using our last attunement slot to embrace absurdity: add another +1d10 from the Sword of Kas, a sentient evil artifact sword.
Now, here's where it gets tricky... The DMG has minor magical properties that can grant an initiative bonus:
Let's say our particular Ioun Stone or Stone of Good Luck has it. Beyond that, it is ultimately up to the DM if other items with these properties show up.
The existence of this property means there is no theoretical ceiling - it doesn't have to be on attunement-required items. I know of at least two that exist in Adventures League play - a hand crossbow and a shield - and there may be more. There is the question of stacking effects, too. Is the Guardian property on two items the "same source"? That's up to the DM to decide.
Grand Total - +56+1d10... or more.
If we restrict the stats to more "normal" ranges, say 20s (for +5), it only drops to +36. No matter how you slice it, if you deliberately build a character with the express intent to "go first every time", you can overwhelm the variable d20 with static bonuses. Of course, the character may not have anything worth doing when they go first, and after the first round it doesn't really matter all that much.
1Being a Chronurgist also gives you access to Gift of Alacrity, a first level non-concentration spell that provides 1d8 to initiative for 8 hours. But that's temporary, so it doesn't count in the total.
2Both abilities here specify "that doesn’t already use your proficiency bonus". If you interpret using half the bonus doesn't count as "already us[ing] your proficiency bonus", then you could have both for another +3.
3If half-proficiency is acquired via Bard, there's room for Barbarian 7 for built-in advantage on Initiative from Feral Instinct, but you either wouldn't have Heavy Armor Proficiency to wear the Scorpion Plate, or you'd have to burn a feat for it.