Exhibit 4.3


 


[FACE]


 


Number


 


Warrants


 


THIS WARRANT SHALL BE VOID IF NOT EXERCISED
PRIOR TO

THE EXPIRATION OF THE EXERCISE PERIOD PROVIDED FOR

IN THE WARRANT AGREEMENT DESCRIBED BELOW


 


Onyx Acquisition Co. I

Incorporated Under the Laws of the Cayman Islands


 


CUSIP [           ]


 


Warrant Certificate


 


This Warrant Certificate certifies that
[          ], or registered assigns, is the registered holder of [            ]
warrant(s) evidenced hereby (the “Warrants” and each, a “Warrant”) to purchase Class
A ordinary shares, $0.0001 par value per share (“Ordinary Shares”), of Onyx Acquisition Co. I, a Cayman Islands
exempted company (the “Company”). Each Warrant entitles the holder, upon exercise during the period set forth
in the Warrant Agreement referred to below, to receive from the Company that number of fully paid and non-assessable Ordinary Shares as
set forth below, at the exercise price (the “Exercise Price”) as determined pursuant to the Warrant Agreement,
payable in lawful money (or through “cashless exercise” as provided for in the Warrant Agreement) of the United
States of America upon surrender of this Warrant Certificate and payment of the Exercise Price at the office or agency of the Warrant
Agent referred to below, subject to the conditions set forth herein and in the Warrant Agreement. Defined terms used in this Warrant Certificate
but not defined herein shall have the meanings given to them in the Warrant Agreement.


 


Each whole Warrant is initially exercisable for
one fully paid and non-assessable Ordinary Share. No fractional shares will be issued upon exercise of any Warrant. If, upon the exercise
of Warrants, a holder would be entitled to receive a fractional interest in an Ordinary Share, the Company will, upon exercise, round
down to the nearest whole number of the number of Ordinary Shares to be issued to the holder. The number of Ordinary Shares issuable upon
exercise of the Warrants is subject to adjustment upon the occurrence of certain events as set forth in the Warrant Agreement.


 


The initial Exercise Price per Ordinary Share for
any Warrant is equal to $11.50 per share. The Exercise Price is subject to adjustment upon the occurrence of certain events as set forth
in the Warrant Agreement.


 


Subject to the conditions set forth in the Warrant
Agreement, the Warrants may be exercised only during the Exercise Period and to the extent not exercised by the end of such Exercise Period,
such Warrants shall become void. The Warrants may be redeemed, subject to certain conditions, as set forth in the Warrant Agreement.


 


Reference is hereby made to the further provisions
of this Warrant Certificate set forth on the reverse hereof and such further provisions shall for all purposes have the same effect as
though fully set forth at this place.


 


This Warrant Certificate shall not be valid unless
countersigned by the Warrant Agent, as such term is used in the Warrant Agreement.


 


This Warrant Certificate shall be governed by and
construed in accordance with the internal laws of the State of New York, without regard to conflicts of laws principles thereof.


 


	 	ONYX ACQUISITION CO. I
	 	 	 
	 	By:	 
	 	Name: 	Michael Stern
	 	Title:	Director, Chairman and Chief Executive Officer
	 	 	 
	 	CONTINENTAL STOCK TRANSFER & TRUST COMPANY, AS WARRANT AGENT
	 	 	 
	 	By:	 
	 	Name:	 
	 	Title:	Authorized Signatory



 




     


     


    

 


[Form of Warrant Certificate]


 


[Reverse]


 


The Warrants evidenced by this Warrant Certificate
are part of a duly authorized issue of Warrants entitling the holder on exercise to receive [        ]
Ordinary Shares and are issued or to be issued pursuant to a Warrant Agreement dated as of , 2021 (the “Warrant Agreement”),
duly executed and delivered by the Company to Continental Stock Transfer & Trust Company, a New York corporation, as warrant agent
(the “Warrant Agent”), which Warrant Agreement is hereby incorporated by reference in and made a part of this
instrument and is hereby referred to for a description of the rights, limitation of rights, obligations, duties and immunities thereunder
of the Warrant Agent, the Company and the holders (the words “holders” or “holder”
meaning the Registered Holders or Registered Holder, respectively) of the Warrants. A copy of the Warrant Agreement may be obtained by
the holder hereof upon written request to the Company. Defined terms used in this Warrant Certificate but not defined herein shall have
the meanings given to them in the Warrant Agreement.


 


Warrants may be exercised at any time during the
Exercise Period set forth in the Warrant Agreement. The holder of Warrants evidenced by this Warrant Certificate may exercise them by
surrendering this Warrant Certificate, with the form of election to purchase set forth hereon properly completed and executed, together
with payment of the Exercise Price as specified in the Warrant Agreement (or through “cashless exercise” as provided for in
the Warrant Agreement) at the principal corporate trust office of the Warrant Agent. In the event that upon any exercise of Warrants evidenced
hereby the number of Warrants exercised shall be less than the total number of Warrants evidenced hereby, there shall be issued to the
holder hereof or his, her or its assignee, a new Warrant Certificate evidencing the number of Warrants not exercised.


 


Notwithstanding anything else in this Warrant Certificate
or the Warrant Agreement, no Warrant may be exercised unless at the time of exercise (i) a registration statement covering the issuance
of the Ordinary Shares to be issued upon exercise is effective under the Securities Act and (ii) a prospectus thereunder relating to the
Ordinary Shares is current, except through “cashless exercise” as provided for in the Warrant Agreement.


 


The Warrant Agreement provides that upon the occurrence
of certain events the number of Ordinary Shares issuable upon exercise of the Warrants set forth on the face hereof may, subject to certain
conditions, be adjusted. If, upon exercise of a Warrant, the holder thereof would be entitled to receive a fractional interest in an Ordinary
Share, the Company shall, upon exercise, round down to the nearest whole number of Ordinary Shares to be issued to the holder of the Warrant.


 


Warrant Certificates, when surrendered at the principal
corporate trust office of the Warrant Agent by the Registered Holder thereof in person or by legal representative or attorney duly authorized
in writing, may be exchanged in the manner and subject to the limitations provided in the Warrant Agreement, but without payment of any
service charge, for another Warrant Certificate or Warrant Certificates of like tenor evidencing in the aggregate a like number of Warrants.


 


Upon due presentation for registration of transfer
of this Warrant Certificate at the office of the Warrant Agent a new Warrant Certificate or Warrant Certificates of like tenor and evidencing
in the aggregate a like number of Warrants shall be issued to the transferee(s) in exchange for this Warrant Certificate, subject to the
limitations provided in the Warrant Agreement, without charge except for any tax or other governmental charge imposed in connection therewith.


 


The Company and the Warrant Agent may deem and
treat the Registered Holder(s) hereof as the absolute owner(s) of this Warrant Certificate (notwithstanding any notation of ownership
or other writing hereon made by anyone), for the purpose of any exercise hereof, of any distribution to the holder(s) hereof, and for
all other purposes, and neither the Company nor the Warrant Agent shall be affected by any notice to the contrary. Neither the Warrants
nor this Warrant Certificate entitles any holder hereof to any rights of a shareholder of the Company.


 




    2


     


    

 


Election to Purchase


 


(To Be Executed
Upon Exercise of Warrant)


 


The undersigned hereby irrevocably elects to exercise
the right, represented by this Warrant Certificate, to receive Ordinary Shares and herewith tenders payment for such Ordinary Shares to
the order of Onyx Acquisition Co. I (the “Company”) in the amount of $[_______] in accordance with the terms hereof.
The undersigned requests that a certificate for such Ordinary Shares be registered in the name of [____], whose address is [_______] and
that such Ordinary Shares be delivered to[_____], whose address is [____]. If said number of Ordinary Shares is less than all of the Ordinary
Shares purchasable hereunder, the undersigned requests that a new Warrant Certificate representing the remaining balance of such Ordinary
Shares be registered in the name of [____], whose address is [____] and that such Warrant Certificate be delivered to [____], whose address
is [____].


 


In the event that the Warrant has been called for
redemption by the Company pursuant to Section 6.1 of the Warrant Agreement and the Company has required cashless exercise pursuant
to Section 6.3 of the Warrant Agreement, the number of Ordinary Shares that this Warrant is exercisable for shall be determined
in accordance with subsection 3.3.1(b) and Section 6.3 of the Warrant Agreement.


 


In the event that the Warrant is to be exercised
on a “cashless” basis pursuant to Section 7.4 of the Warrant Agreement, the number of Ordinary Shares that this Warrant
is exercisable for shall be determined in accordance with subsection 3.3.1(c) and Section 7.4 of the Warrant Agreement.


 


In the event that the Warrant may be exercised,
to the extent allowed by the Warrant Agreement, through cashless exercise (i) the number of Ordinary Shares that this Warrant is exercisable
for would be determined in accordance with the relevant section of the Warrant Agreement which allows for such cashless exercise and (ii)
the holder hereof shall complete the following: The undersigned hereby irrevocably elects to exercise the right, represented by this Warrant
Certificate, through the cashless exercise provisions of the Warrant Agreement, to receive Ordinary Shares. If said number of shares is
less than all of the Ordinary Shares purchasable hereunder (after giving effect to the cashless exercise), the undersigned requests that
a new Warrant Certificate representing the remaining balance of such Ordinary Shares be registered in the name of [______], whose address
is [_______] and that such Warrant Certificate be delivered to [______], whose address is [____].


 


[Signature Page Follows]


 




    3


     


    

 


	Date:  ________________, 20___	 	 
	 	 	 
	 	 	By:	                  
	 	 	(Signature)
	 	 	 
	 	 	 
	 	 	 
	 	 	 
	 	 	 
	 	 	 
	 	 	 
	 	 	 
	 	 	(Address)
	 	 	 
	 	 	 
	 	 	(Tax Identification Number)
	 	 	 
	Signature Guaranteed:	 	 
	 	 	 
	 	 	 



 


THE SIGNATURE(S) SHOULD BE GUARANTEED BY AN ELIGIBLE GUARANTOR INSTITUTION
(BANKS, STOCKBROKERS, SAVINGS AND LOAN ASSOCIATIONS AND CREDIT UNIONS WITH MEMBERSHIP IN AN APPROVED SIGNATURE GUARANTEE MEDALLION PROGRAM,
PURSUANT TO S.E.C. RULE 17Ad-15 (OR ANY SUCCESSOR RULE)).


 


 


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